all sets combined
What is the formula to identify the required number of WAN connections
"w=n*(n-1)/2" w= the number of WAN links n=the number of sites
A network interface card operates at what layer of the OSI model?
#1 - Physical Layer
Which OSI layer is responsible for the mechanical connection to the network?
#1 - Physical Layer
Which OSI layer is considered the media access control layer?
#2 - Data Link Layer
At what layer does a router work?
#3 - Network Layer
IP and IPX are examples of protocols that operate in what layer of the OSI model?
#3 - Network Layer
What OSI layer is responsible for adding a header that includes routing information?
#3 - Network Layer
Which OSI layer combines messages or segments into packets?
#3 - Network Layer
TCP functions at what layer of the OSI model?
#4 - Transport Layer
Which OSI layer is responsible for data compression and encryption?
#6 - Presentation Layer
HTTP functions at what layer of the OSI model?
#7 - Application Layer
What are the four factors that contribute to attenuation?
(The loss of power introduced by the fiber) -Scattering -Absorption -Macrobending -Microbending
List the basic elements of a fiber-optic communication system.
-A fiber-optic transmission strand -A source of invisible infrared (IR) radiation -A photosensitive detector -Efficient optical connectors at the light source-to-cable interface and the cable-to-photo detector interface.
What are the two kinds of light sources used in fiber-optic communication systems?
-DL = diode laser (usually used as source for single-mode fiber) -LED = light-emitting diode
What are the four physical layer technologies used in 802.11 wireless networking?
-DSSS Direct-sequence spread spectrum -FHSS Frequency-hopping spread spectrum -OFDM Orthogonal frequency-division multiplexing -Infrared
List 5 advantages of an optical communications link.
-Extremely wide system bandwidth -Immunity to electrostatic interference -Elimination of crosstalk -Lower signal attenuation than with other propagation systems -Lower costs -Safety -Corrosion -Security
Describe how a TCP connection is terminated.
-Host A sends a FIN (finish) packet to the other connected host. -Host B sends an ACK packet -Host B sends a FIN packet -Host A sends an ACK packet
What are three types of dispersion?
-Modal dispersion -Chromatic dispersion -Polarization mode dispersion
What are the commonly used wavelengths in fiber-optic systems?
-Multimode fiber: 850 and 1310nm -Single mode fiber: 1310 and 1550nm -Fiber-to-the-home/fiber-to-the-business: 1600-1625nm
What are the three areas defined for the IEEE 802.11 standard?
-Physical Layer -Media Access Control (MAC) Layer -MAC management protocols and services.
Describe the frequency spectrum for the DSSS channels in 802.11b wireless networking.
-Used in 802.11b/g/n -14 channels -
Class A - Public
1-126 ... 255.0.0.0 (/8)
Disadvantages of a Bus topology
1. All devices receive data transmitted 2. If more than one computer tries to transmit at the same time, the data becomes corrupted and has to be retransmitted. 3. Devices have to wait for a pause in transmission to transmit data
What are the four layers of the TCP/IP model?
1. Application Layer 2. Transport Layer 3. Internet Layer 4. Network interface Layer
Identify the six subsystems of a structured cabling system.
1. Building Entrance aka Entrance Facilities (EF) 2. Equipment Room (ER) 3. Telecommunications closet aka Telecommunications Room (TR) 4. Backbone Cabling 5. Horizontal Cabling 6. Work Area
What are three parts of the EIA/TIA 568-B standard?
1. EIA/TIA 568-B.1: Commercial Cabling Standard, Master Document 2. IA/TIA 568-B.2: Twisted-pair Media 3. EIA/TIA 568-B.3: Optical Fiber Cabling Standard
Disadvantages of the Token Ring System
1. If an error changes the token patter, it can cause the token to stop circulating 2. A failed station can cause data traffic to cease 3. To troubleshoot or maintain, the Token Ring path must be broken, resulting in downtime for the network.
What are three advantages of using an active RFID tag?
1. Incorporating wireless Ethernet / 802.11b 2. Low power consumption 3. Location capability
What three frequency bands are typically used for RFID tags?
1. Low-frequency (LF) between 125-134KHz 2. High-frequency (HF) 13.56MHz 3. Ultra-high frequency (UHF), 860-960MHz
What are the three parameters that define and RFID system?
1. Means of powering the tag 2. Frequency of operation 3. Communications protocol (AKA air interface protocol)
List the three types of VLANs?
1. Port-Based - host computers connected to specific ports on a switch are assigned to a specfi VLAN 2. Tag-Based - the VLAN ID is based on 802.1Q 3. Protocol-Based - Connection to ports is based on the protocol being used.
Which two (book shows 3) modes does a switch use to forward frames?
1. Store-and-forward: The entire frame of data is received before any decision is made regarding forwarding. 2. Cut-through: Data is forwarded to the destination as as the destination MAC address has been read. 3. Adaptive cut-through: Combination of store-and-forward and cut-through. The cut-through mode is used until an error threshold has been exceeded and store-and-forward has been used.
Which three packets are exchanged between two hosts when establishing a TCP connection?
1. The SYN (synchronizing packet) 2. The SYN ACK (sync acknowledgement) packet 3. The ACK (acknowledgement) packet
Class A - Private
10.0.0.0-10.255.255.255 /8
What is the overall length limitation of an individual cable run from the telecommunications closet to a networking device in the work area?
100 Meters
What is the data rate for Gigabit Ethernet
1000Mbps
What is the data rate for Fast Ethernet?
100Mbps
The binary 1 0 1 1 0 1 1 0 1 1 1 1 0 0 0 1 converts to what value in hexadecimal? A. B6F1 B. A6F1 C. AAF1 D. BAF1 E. None of these answers is correct.
1011 0110 1111 0001 B 6 F 1 A. B6F1
Convert 1011011011110001 to hexadecimal.
1011 0110 1111 0001 B 6 F 1
What is the data rate for Ethernet?
10Mbps
Convert the number 65 to its binary equivalent.
128 64 32 16 8 4 2 1 0 1 0 0 0 0 0 1 01000001
Convert the number 96 to its binary equivalent.
128 64 32 16 8 4 2 1 0 1 1 0 0 0 0 0 01100000
Convert the following 8-bit binary number to decimal: 10010011
128 64 32 16 8 4 2 1 1 0 0 1 0 0 1 1 128 + 16 + 2 + 1 = 147
Convert the number 192 to its binary equivalent.
128 64 32 16 8 4 2 1 1 1 0 0 0 0 0 0 11000000
True or false: Converting 65 to its binary equivalent yields 1 0 0 0 0 0 1
128 64 32 16 8 4 2 1 0 1 0 0 0 0 0 1'' 01000001 False
Convert the following octet to decimal: 11000000
128 64 32 16 8 4 2 1 1 1 0 0 0 0 0 0 128 + 64 = 192
Convert the following 8-bit number to decimal: 11111100
128 64 32 16 8 4 2 1 1 1 1 1 1 1 0 0 128+64+32+16+8+4 = 252
Convert the following binary number to decimal: 11111111
128 64 32 16 8 4 2 1 1 1 1 1 1 1 1 1 =255
Class B - Public
128-191 ... 255.255.0.0 (/16)
A router on a home network is assigned the IP address 128.123.45.67. A computer in the home network is assigned the private IP address 192.168.10.62. This computer is assigned the public IP address 128.123.45.67:1922. Which IP address is used for routing data packets on the Internet? Is overloading being used?
128.123.45.67 is being used for routing data packets on the Internet.
Class B - Private (APIPA)
169.254.0.0-169.254.255.255 /16
Class B - Private
172.16.0.0-172.31.255.255 /16
Class C - Public
192-223 ... 255.255.255.0 (/24)
What is the IP address range for Class C addresses?
192.0.0.0 - 223.255.255.255
Class C - Private
192.168.0.0-192.168.255.255 /24
How many host bits are borrowed if four subnets are created?
2 bits
802.11n
2.4 or 5 GHz (or both) / > 300Mbps / OFDM / 70 m in or 250 m out
802.11
2.4GHz / 1 or 2Mbps / DSSS or FHSS / 20 m indoors or 100 m outdoors
802.11b
2.4GHz / 11Mbps / DSSS / 32 m in or 140 m out
802.11g
2.4GHz / 54 Mbps / OFDM or DSSS / 32 m in or 140 m out
In what frequency band does Bluetooth operate?
2.4Ghz
Class D - Public
224-239 (destination IP addresses for multicast networks)
Class E - Public
240-255 (experimental use IP addresses)
How many bits are in an IPv4 address? How many octets?
4 8-bit octets, 32 bits total
How many wire pairs are in a CAT6 twisted-pair cable?
4 twisted wire pairs (8 wires)
How many wires are in a CAT6 twisted-pair cable?
4 twisted wire pairs (8 wires)
Convert 0x5AF3 to binary. (Use table 6-6)
5 A F 3 0101 1010 1111 0011
802.11a
5 GHz / 54Mbps / OFDM / 35 m in or 120 m out
What is the WiMAX frequency standard for the US?
5.8GHz (unlicensed), 2.5GHz (licensed)
802.11ac
5GHz / > 3Gbps / OFDM / 70 m in or 250 m out
What is the minimum size of the data payload in an Ethernet frame?
64 bytes
What is the typical core size for single-mode fiber?
7-10
What are the 7 layers of the OSI Model
7. Application 6. Presentation. 5. Session 4. Transport 3. Network 2. Data link 1. Physical
How many pins does an RJ-45 plug have?
8 pins
What is the proper term for the RJ-45 modular plug?
8p8c
A general rule of thumb is to allow how many meters for the cable run from the telecommunications closet to the work area?
90 meters
APC (angle polished connector)
A connector commonly used with fiber cables—usually single mode—to keep the signal from bouncing back down the line.
AUP (acceptable use policy)
A policy created by an organization defining what is acceptable on their resources (network, computers, and so on).
10GBaseT
A 2006 standard to provide 10 Gbps connections over unshielded or shielded twisted pair cables, over distances up to 100 meters using category 6a (category 6 can reach 55 meters).
Basic Rate Interface (BRI)
A BRI circuit contains two 64-kbps B channels and one 16-Kbps D channel. although such a circuit can carry two simultaneous voice conversations, the two B channels can be logically bonded together into a single virtual circuit (by using PPP's multilink interface feature) to offer a 128-kbps data path.
Enhanced Interior Gateway Routing Protocol (EIGRP)
A Cisco proprietary protocol. So although EIGRP is popular in Cisco-only networks, it is less popular in mixed-vendor networks. Like OSPF, EIGRP is an IGP with very fast convergence and is very scalable. EIGRP is considered to be an advanced distance vector or a hybrid routing protocol.
denial of service (DoS)
A DoS attack floods a system with an excessive amount of traffic or requests, which consumes the system's processing resources and prevents the system from responding to many legitimate requests.
host-based IPS (HIPS)
A HIPS system is a computer running intrusion prevention software for the purpose of protecting the computer from attacks.
Synchronous Optical Network (SONET)
A Layer 1 technology that uses fiber-optic cabling as its media. Because SONET is a Layer 1 technology, it can be used to transport various Layer 2 encapsulation types, such as ATM. Also, because SONET uses fiber-optic cabling, it offers high data rates, typically in the 155-Mbps to 10-Gbps range, and long-distance limitations, typically in the 20-km to 250-km range.
Asynchronous Transfer Mode (ATM)
A Layer 2 WAN technology that interconnects sites using virtual circuits. These virtual circuits are identified by a pair of numbers, called the VPI/VCI pair. A virtual path identifier (VPI) identifies a logical path, which can contain multiple virtual circuits. A virtual circuit identifier (VCI) identifies the unique logical circuit within a virtual path.
Frame Relay
A Layer 2 WAN technology that interconnects sites using virtual circuits. These virtual circuits are identified by locally significant data-link connection identifiers (DLCI).
Real-time Transport Protocol (RTP)
A Layer 4 protocol that carries voice (and interactive video).
ipconfig command
A Microsoft Windows command that can be used to display IP address configuration parameters on a PC. In addition, if DHCP is used by the PC, the ipconfig command can be used to release and renew a DHCP lease, which is often useful during troubleshooting.
Microsoft Routing and Remote Access Server (RRAS)
A Microsoft Windows server feature that allows Microsoft Windows clients to remotely access a Microsoft Windows network.
Tracert command
A Microsoft Windows-based command that displays every router hop along the path from a source host to a destination host on an IP network. Information about a router hop can include such information as the IP address of the router hop and the round-trip delay of that router hop.
Microsoft Challenge Handshake Authentication Protocol (MS-CHAP)
A Microsoft-enhanced version of CHAP, offering a collection of additional features not present with PAP or CHAP, including two-way authentication.
network-based IDS (NIDS)
A NIDS device is a network appliance dedicated to the purpose of acting as an IDS sensor.
network-based IPS (NIPS)
A NIPS device is a network appliance dedicated to the purpose of acting as an IPS sensor.
Why are the layers of the OSI model important to a network administrator?
A Network Admin needs to have a good understanding of ALL seven layers of the OSI model. Knowledge of the layers can help isolate network problems.
public key infrastructure (PKI)
A PKI system uses digital certificates and a certificate authority to allow secure communication across a public network.
plain old telephone service (POTS)
A POTS connection connects a customer device (such as a telephone) to the public switched telephone network (PSTN).
primary rate interface (PRI)
A PRI circuit is an ISDN circuit built on a T1 or E1 circuit. Recall that a T1 circuit has 24 channels. Therefore, if a PRI circuit is built on a T1 circuit, the ISDN circuit has 23 B channels and a one 64-Kbps D channel. The 24th channel in the T1 circuit is used as the ISDN D channel (that is, the channel used to carry the Q.921 and Q.931 signaling protocols, which are used to set up, maintain, and tear down connections).
Terminal Access Controller Access-Control System Plus (TACACS+)
A TCP-based protocol used to communicate with a AAA server. Unlike RADIUS, TACACS+ encrypts an entire authentication packet rather than just the password. TACACS+ offers authentication features, but they are not as robust as the accounting features found in RADIUS. Also, unlike RADIUS, TACACS+ is a Cisco-proprietary protocol.
Remote Authentication Dial-In User Service (RADIUS)
A UDP-based protocol used to communicate with a AAA server. Unlike TACACS+, RADIUS does not encrypt an entire authentication packet, but only the password. However, RADIUS offers more robust accounting features than TACACS+. Also, RADIUS is a standards-based protocol, whereas TACACS+ is a Cisco proprietary protocol.
What is a VPN, and how does it protect data transferred over a wireless network?
A VPN is a Virtual Private Network. It's a secure network connection that helps protect your LAN's data from being observed by outsiders. The VPN connection is encrypted, providing privacy for the data packets being transmitted.
Layer 2 Forwarding (L2F)
A VPN protocol designed (by Cisco Systems) with the intent of providing a tunneling protocol for PPP. Like L2TP, L2F lacks native security features.
Layer 2 Tunneling Protocol (L2TP)
A VPN protocol that lacks security features, such as encryption. However, L2TP can still be used for a secure VPN connection if it is combined with another protocol that provides encryption.
Session Initiation Protocol (SIP)
A VoIP signaling protocol used to set up, maintain, and tear down VoIP phone calls.
Multiprotocol Label Switching (MPLS)
A WAN technology popular among service providers. MPLS performs labels switching to forward traffic within an MPLS cloud by inserting a 32-bit header (which contains a 20-bit label) between a frame's Layer 2 and Layer 3 headers and making forwarding decisions based on the label within an MPLS header.
independent basic service set (IBSS)
A WLAN can be created without the use of an AP. Such a configuration, called an IBSS, is said to work in an ad-hoc fashion. An ad hoc WLAN is useful for temporary connections between wireless devices. For example, you might temporarily interconnect two laptop computers to transfer a few files.
binary
A base 2 numbering system used in digital signaling. It uses only the numbers 1 and 0.
Open
A broken strand of copper that prevents current from flowing through a circuit.
central office (CO)
A building containing a telephone company's telephone-switching equipment is referred to as a central office (CO). COs are categorized into five hierarchical classes. A Class 1 CO is a long-distance office serving a regional area. A Class 2 CO is a second-level long-distance office; that is, it is subordinate to a Class 1 office. A Class 3 CO is a third-level long-distance office. A Class 4 CO is a fourth-level long-distance office, which provides telephone subscribers access to a live operator. A Class 5 CO is at the bottom of the five-layer hierarchy and physically connects to customer devices in a local area.
What is the "two-deep" rule?
A building should have only the main distribution and the intermediate distribution that feeds the horizontal distribution to the work area.
What is the purpose of the fast link pulse?
A burst (10Mbps, 10BASE-T) that carries configuration information between each end of a data link.
What is Crossover Cable?
A cable in which the transmit and receive wire pairs are crossed.
What is a straight-through cable?
A cable in which the wire pairs in the cable connect to the same pin numbers on each side.
cable tester
A cable tester can test the conductors in an Ethernet cable. It contains two parts. By connecting these parts of the cable tester to each end of a cable under test, you can check the wires in the cable for continuity (that is, check to make sure that there are no opens, or breaks, in a conductor). I In addition, you can verify an RJ-45 connector's pinouts (which are wires connected to the appropriate pins on an RJ-45 connector).
What is a rollover cable?
A cable with the signals reverse at each end. (Console cable)
link state
A category of routing protocol that maintains a topology of a network and uses an algorithm to determine the shortest path to a destination network.
distance vector
A category of routing protocol that sends a full copy of its routing table to its directly attached neighbors.
classful mask
A classful mask is the default subnet mask applied to Class A, B, and C IPv4 networks. Specifically, Class A networks have a classful mask of 255.0.0.0. Class B networks have a classful mask of 255.255.0.0, and Class C networks have a classful mask of 255.255.255.0.
Kerberos
A client-server authentication protocol that supports mutual authentication between a client and a server. Kerberos uses the concept of a trusted third party (a key distribution center) that hands out tickets to be used instead of a username and password combination.
AS (autonomous system)
A collection of connected IP routing prefixes under the control of a network administrator or entity that offers a common and defined routing policy to the Internet
Collision
A collision occurs when two devices on an Ethernet network simultaneously transmit a frame. Because an Ethernet segment cannot handle more than one frame at a time, both frames become corrupted.
Point-to-Point Protocol (PPP)
A common Layer 2 protocol offering features such as multilink interface, looped link detection, error detection, and authentication.
Challenge-Response Authentication Mechanism Message Digest 5 (CRAM-MD5)
A common variant of HMAC frequently used in e-mail systems. Like CHAP, CRAM-MD5 only performs one-way authentication (the server authenticates the client).
software firewall
A computer running firewall software. For example, the software firewall could protect the computer itself (for example, preventing incoming connections to the computer). Alternatively, a software firewall could be a computer with more than one network interface card that runs firewall software to filter traffic flowing through the computer.
local loop
A connection between a customer premise and a local telephone company's central office.
circuit-switched connection
A connection that is brought up on an as-needed basis. A circuit-switched connection is analogous to phone call, where you pick up a phone, dial a number, and a connection is established based on the number you dial.
Transmission Control Protocol (TCP0
A connection-oriented transport protocol. Connection-oriented transport protocols provide reliable transport, in that if a segment is dropped, the sender can detect that drop and retransmit that dropped segment. Specifically, a receiver acknowledges segments that it receives. Based on those acknowledgments, a sender can determine which segments were successfully received.
User Datagram Protocol (UDP)
A connectionless transport protocol. Connectionless transport protocols provide unreliable transport, in that if a segment is dropped, the sender is unaware of the drop, and no retransmission occurs.
security policy
A continually changing document that dictates a set of guidelines for network use. These guidelines complement organizational objectives by specifying rules for how a network is used.
content engine
A dedicated appliance whose role is to locally cache content received from a remote network (for example, a destination on the Internet). Subsequent requests for that content can be serviced locally, from the content engine, thus reducing bandwidth demand on a WAN.
default static route
A default static route is an administratively configured entry in a router's routing table that specifies where traffic for all unknown networks should be sent.
Hub
A device that broadcasts the data it receives to all devices connected to its ports
wireless access point (AP)
A device that connects to a wired network and provides access to that wired network for clients that wirelessly attach to the AP.
Switch
A device that forwards a frame it receives directly ou tth eport associated with its destination address
E3
A digital circuit in the same E-carrier family of standards as an E1. An E3 circuit's available bandwidth is 34.4 Mbps.
Integrated Services Digital Network (ISDN)
A digital telephony technology that supports multiple 64-kbps channels (known as bearer channels or B channels) on a single connection. ISDN was popular back in the 1980s for connecting PBXs, which are telephone switches owned and operated by a company, to a telephone company's central office. ISDN has the ability to carry voice, video, or data over its B channels. ISDN also offers a robust set of signaling protocols: Q.921 for Layer 2 signaling and Q.931 for Layer 3 signaling. These signaling protocols run on a separate channel in an ISDN circuit (known as the delta channel, data channel, or D channel).
Routing Information Protocol (RIP)
A distance-vector routing protocol that uses a metric of hop count. The maximum number of hops between two routers in an RIP-based network is 15. Therefore, a hop count of 16 is considered to be infinite. RIP is considered to be an IGP.
backup schedule
A document or plan that defines what type of backups are made, when, and what data is backed up.
1000BaseSX
A fiber optic Gigabit Ethernet standard for operation over multimode fiber.
unified threat management (UTM)
A firewall or gateway that attempts to bundle multiple security functions into a single physical or logical device.
archive bit
A flag that is set on a file after it has been created or altered. Some backup methods reset the flag to indicate that it has been backed up.
GNU privacy guard (GPC)
A free variant of pretty good privacy (PGP), which is an asymmetric encryption algorithm.
What is a Wiremap?
A graphical or text description of the wire connections from pin to pin
array
A group of devices arranged in a fault-tolerant configuration. See also RAID.
digital subscriber line (DSL)
A group of technologies that provide high-speed data transmission over existing telephone wiring. DSL has several variants, which vary in data rates and distance limitations. Three of the more popular DSL variants include asymmetric DSL (ADSL), symmetric DSL (DSL), and very high bit-rate DSL (VDSL).
Octet
A grouping of 8 bits. An IPv4 address consists of four octets (that is, a total of 32 bits).
half duplex
A half-duplex connection allows a device to either receive or transmit data at any one time. However, a half-duplex device cannot simultaneously transmit and receive.
How is IP addressing typically handled in a home network?
A home network typically only has one connection to the ISP, but multiple computers can be connected to the Internet at the same time. IP addresses is managed by the router or wireless router that connects to the ISP. The ISP issues an IP address to the router or wireless router from an available pool of IP address managed by the ISP. The computers in the home network are issued private IP addresses by the router or wireless router.
What is the difference between a hub and a switch?
A hub broadcasts data transmission to all devices connected to its ports, while a switch will forward to the device / port associated with the destination address in the frame
Why does a switch offer better security than a hub?
A hub forwards the data it receives to every device connected to the hub. It is possible for the network device to pick up dataa intended for a different device. A switch eliminates this by only forwarding data packets to the correct devices whenever possible.
active hub
A hub that has power supplied to it for the purposes of regenerating the signals that pass through it.
Token Ring Hub
A hub that manages the passing of the token in a Token Ring network. Manages the passing of token instead of relying on the individual computers to pass it (improves reliability of the network)
partial-mesh topology
A hybrid of a hub-and-spoke topology and a full-mesh topology. A partial-mesh topology can be designed to provide an optimal route between selected sites, while avoiding the expense of interconnecting every site to every other site.
Why is a tunable laser of importance in optical networking?
A laser in which the fundamental wavelength can be shifted a few nanometers, which is ideal for traffic routing in DWDM systems. DWDM = Dense Wavelength Division Multiplexing
Bootstrap Protocol (BOOTP)
A legacy broadcast-based protocol used by networked devices to obtain IP address information.
What is a hotspot?
A limited geographic area that provides wireless access for the public
link-local IP address
A link-local IP address is a nonroutable IP address usable only on a local subnet.
Intermediate System-to-Intermediate System (IS-IS)
A link-state routing protocol similar in its operation to OSPF. IS-IS uses a configurable, yet dimensionless, metric associated with an interface and runs Dijkstra's shortest path first algorithm. Although using IS-IS as an IGP offers the scalability, fast convergence, and vendor interoperability benefits of OSPF, it has not been deployed as widely as OSPF.
Open Shortest Path First (OSPF)
A link-state routing protocol that uses a metric of cost, which is based on the link speed between two routers. OSPF is a popular IGP because of its scalability, fast convergence, and vendor interoperability.
What information is stored in a bridge table?
A list of MAC addresses and port locations for hosts connected to the bridge ports.
application log
A log file on a Windows system that provides information on events that occur within an application.
dedicated leased line
A logical connection interconnecting two sites. This logical connection might physically connect through a service provider's facility or a telephone company's central office. The expense of a dedicated leased line is typically higher than other WAN technologies offering similar data rates, because with a dedicated leased line, a customer does not have to share bandwidth with other customers.
decibel (dB) loss
A loss of signal power. If a transmission's dB loss is too great, the transmission cannot be properly interpreted by the intended recipient.
cyclic redundancy check (CRC)
A mathematical algorithm that is executed on a data string by both the sender and receiver of the data string. If the calculated CRC values match, the receiver can conclude that the data string was not corrupted during transmission.
Baseline
A measurement of performance of a device or system for the purposes of future comparison. Baselining is a common server administration task. A collection of data portraying the characteristics of a network under normal operating conditions. Data collected while troubleshooting can then be contrasted against baseline data.
prefix notation
A method of indicating how many bits are in a subnet mask. For example, /24 is prefix notation for a 24-bit subnet mask. Prefix notation is also known as slash notation.
dotted-decimal notation
A method of writing an IPv4 address or subnet mask, where groups of 8 bits (called octets) are separated by periods.
Define "full-duplex".
A mode in which a communications device can transmit and receive at the same time.
Define "half-duplex".
A mode in which a communications device can transmit or receive, but not both at the same time.
Multicast
A multicast communication flow is a one-to-many flow.
Internet Group Management Protocol (IGMP)
A multicast protocol used between clients and routers to let routers know which of their interfaces has a multicast receiver attached.
Protocol Independent Multicast (PIM)
A multicast protocol used between multicast-enabled routers to construct a multicast distribution tree.
hardware firewall
A network appliance dedicated to the purpose of acting as a firewall. This appliance can have multiple interfaces for connecting to areas of a network requiring varying levels of security.
honey net
A network containing more than one honey pot.
backbone
A network segment that acts as a trunk between other network segments. Backbones typically are high-bandwidth implementations, such as fiber-optic cable.
Token Ring Topology
A network topology configured in a logical ring that complements the token passing protocol
personal-area network (PAN)
A network whose scale is smaller than a LAN. As an example, a connection between a PC and a digital camera via a USB cable is considered to be a PAN.
Nessus
A network-vulnerability scanner available from Tenable Network Security.
Nmap
A network-vulnerability scanner.
What is a bridge?
A networking device (layer 2) that uses MAC address information to forward data and interconnect LANs
Define the term gateway.
A networking device that enables hosts in a LAN to connect to networks (and hosts) outside the LAN.
next hop
A next-hop IP address is an IP address on the next router to which traffic should be forwarded.
ATM (Asynchronous Transfer Mode)
A packet-switching technology that provides transfer speeds ranging from 1.544 Mbps to 622 Mbps.
administrator
A person responsible for the control and security of the user accounts, resources, and data on a network.
butt set
A piece of test equipment typically used by telephone technicians. The clips on a butt set can connect to the tip and ring wires on a punch-down block (for example, a 66 block or a 110 block) connecting to a telephone. This allows the technician to check the line (for example, to determine whether a dial tone is present on the line and determine whether a call can be placed from the line).
RSA
A popular and widely deployed asymmetric encryption algorithm.
What is an uplink port?
A port that allows the connection of a switch to another switch without requiring a crossover cable. A straight-through port
trouble ticket
A problem report explaining the details of an issue being experienced in a network.
Define "dynamic assignment" on a switch.
A process in which MAC addresses are assigned to a port when a host is connected.
Address Resolution Protocol (ARP)
A protocol in the TCP/IP suite used to resolve IP addresses to MAC addresses. Specifically, the ARP command returns a Layer 2 address for a Layer 3 address.
Simple Network Management Protocol (SNMP)
A protocol used to monitor and manage network devices, such as routers, switches, and servers.
Internet Key Exchange (IKE)
A protocol used to set up an IPsec session.
routed protocol
A protocol with an addressing scheme (for example, IP) that defines different network addresses.
decibel (dB)
A ratio of radiated power to a reference value. In the case of dBi, the reference value is the signal strength (that is, the power) radiated from an isotropic antenna, which represents a theoretical antenna that radiates an equal amount of power in all directions (in a spherical pattern). An isotropic antenna is considered to have gain of 0 dBi.
Router
A router is considered a Layer 3 device, meaning that it makes its forwarding decisions based on logical network addresses. Most modern networks use IP addressing.
black-hole router
A router that drops packets that cannot be fragmented and are exceeding the MTU size of an interface without notifying the sender.
routing protocol
A routing protocol (for example, RIP, OSPF, or EIGRP) that advertises route information between routers, which describes how to reach specified destination networks.
Exterior Gateway Protocol (EGP)
A routing protocol that operates between autonomous systems, which are networks under different administrative control. Border Gateway Protocol (BGP) is the only EGP in widespread use today.
Administrative distance (AD)
A routing protocol's index of believability. Routing protocols with a smaller AD are considered more believable that routing protocols with a higher AD.
Wired Equivalent Privacy (WEP)
A security standard for WLANs. With WEP, an AP is configured with a static WEP key. Wireless clients needing to associate with an AP are configured with an identical key (making this a preshared key [PSK] approach to security). The IEEE 802.11 standard specifies a 40-bit WEP key, which is considered to be a relatively weak security measure.
Define segment.
A segment is a section of a network separated by bridges, switches, and routers.
network as a service (NaaS)
A service provider offering where clients can purchase data services (for example, e-mail, LDAP, and DNS services) traditionally hosted in a corporate data center.
ADSL (asymmetric digital subscriber line)
A service that transmits digital voice and data over existing (analog) phone lines.
address
A set of numbers used to identify and locate a resource or device on a network. An example is an IP address such as 192.168.2.1.
Define the term Protocol
A set of rules established for users to exchange information
Short
A short occurs when two copper connectors touch each other, resulting in current flowing through that short rather than the attached electrical circuit, because the short has lower resistance.
virtual LAN (VLAN)
A single broadcast domain, representing a single subnet. Typically, a group of ports on a switch are assigned to a single VLAN. For traffic to travel between two VLANs, that traffic needs to be routed.
antivirus software
A software application that detects and removes viruses.
What is Cross-connect (Structured Cabling System)?
A space where you are going to take one or multiple cables and conect them to one or more cables or equipment.
1000BaseLX
A standard for Gigabit Ethernet intended for use with long-wavelength (LX) transmissions over long cable runs of fiber optic cabling.
service set identifier (SSID)
A string of characters that identify a WLAN. Aps participating in the same WLAN can be configured with identical SSIDs. An SSID shared among multiple APs is called an extended service set identifier (ESSID).
Syslog
A syslog-logging solution consists of two primary components: syslog servers, which receive and store log messages sent from syslog clients; and syslog clients, which can be a variety of network devices that send logging information to a syslog server.
Bus Topology
A system in which the computers share the media for data transmission
ARP table
A table of entries used by ARP to store resolved ARP requests. Entries can also be manually stored
Token Passing
A technique in which an eletrical token circulates around a network, and control of the token enables the user to gain access to the network
Automatic Private IP Addressing (APIPA)
A technology implemented on certain Windows platforms through which a system assigns itself an IP address in the absence of a DHCP server. Addresses are assigned from the 169.254.x.x address range. Allows a networked device to self-assign an IP address from the 169.254.0.0/16 network. Note that this address is only usable on the device's local subnet (meaning that the IP address is not routable).
Zeroconf
A technology that performs three basic functions: assigning link-local IP addresses, resolving computer names to IP addresses, and locating network services.
Telco
A telephone company. Some countries have government-maintained telcos, and other countries have multiple telcos that compete with one another.
baseband
A term applied to any medium that can carry only a single data signal at a time. Compare with broadband.
BERT (bit-error rate test)
A test to see the number of received bits of a data stream that has changed due to noise, interference, or other distortion.
Mesh Topology
A topology in which all networking devices are directly connected to each other
IP Security (IPsec)
A type of VPN that provides confidentiality, integrity, and authentication.
What is a stateful packet inspection?
A type of firewall that inspects incoming data packets to make sure they correspond to an outgoing requests.
Define the term Deterministic
A type of network in which access to the network is provided at fixed time intervals
Define the purpose of a connection-oriented protocol and give an example.
A type of protocol that establishes network connections, managed the delivery of data, and terminates connections. Example: TCP = Transport Control Protocol
Unicast
A unicast communication flow is a one-to-one flow.
Metric
A value assigned to a route, and lower metrics are preferred over higher metrics.
Static NAT (SNAT)
A variant of NAT in which an inside local IP address is statically mapped to an inside global IP address. SNAT is useful for servers inside a network, which need to be accessible from an outside network.
Dynamic NAT (DNAT)
A variant of NAT in which inside local addresses are automatically assigned an inside global address from a pool of available addresses.
Port Address Translation (PAT)
A variant of NAT in which multiple inside local IP addresses share a single inside global IP address. PAT can distinguish between different flows based on port numbers.
ASP (application service provider)
A vendor who provides computer-based services over the network.
virtual desktop
A virtual desktop solution allows a user to store data in a centralized data center, as opposed to the hard drive of their local computer. Then, with appropriate authentication credentials, that user can access his data from various remote devices (for example, his smartphone or another computer).
Identify the port numbers for the following applications: A. Telnet B. HTTP C. FTP D. DNS E. DHCP
A. 23 B. 80 C. 20/21 D. 53 E. 67/68
What is the maximum data rate for each of the following? A. 802.11b B. 802.11a C. 802.11g D. 802.11n E. 802.11ac
A. 54Mbps B. 11Mbps C. 54Mbps D. 200Mbps E. 1Gbps
Which of the following best define "bridge table". A. A list of MAC addreses and port locations for hosts connected to the bridge ports. B. A list of IP addresses and port locations for hosts connected to the bridge ports. C. A list of IP addresses and port locations for hosts connected to the hub ports. D. A list of MAC addresses and port locations for hosts connected to the hub ports.
A. A list of MAC addresses and port locations for hosts connected to the bridge ports.
Which of the following is the best way to extend the radio range of a station's wireless link with one access point? A. Add multiple access points B. Add additional wiring C. Add 87BZs encoding D. Add B8ZS encoding
A. Add multiple access points.
Which layer of the TCP/IP model processes requests from hosts to ensure that a connection is made to the appropriate port? A. Application B. Internet C. Transport D. None of these answers is correct.
A. Application
Which of the following is a table of MAC addresses and port mapping used by a switch to identify connected network devices? A. CAM B. ARP C. ARP-A D. ipconfig /all
A. CAM = Content Addressable Memory
Which of the following best defines horizontal cabling? A. Cabling that extends out from the telecommunications closet into the LAN work area. B. Cabling that extends out from the work area into the LAN. C. Cabling that extends out from the backbone into the LAN work area D. Cabling that extends out from the equipment room into the LAN work area. E. None of these answers is correct.
A. Cabling that extends out from the telecommunications closet into the LAN work area.
State the class of address (A, B, or C) for each of the following IP address. A. 46.39.42.05 B. 220.244.38.168 C. 198.1.0.4 D. 126.87.12.34 E. 99.150.200.251 F. 128.64.32.16
A. Class A B. Class C C. Class B D. Class A E. Class A F. Class B
How many network bits are in each of the following classes? A. Class A B. Class B C. Class C
A. Class A = 8 bits (24 for host) B. Class B = 16 bits (16 for host) C. Class c = 24 bits (8 for host)
Which of the following are advantages of 802.11g? (select all that apply.) A. Compatible with 802.11b B. Compatible with 802.11a C. Uses infrared instead of radio D. High speed
A. Compatible with 802.11b D. High Speed
Which switch mode offers the minimum switch latency? A. Cut-through B. Fast-forward C. Store-and-forward D. Adaptive cut-through
A. Cut-through
The designation E0 indicates A. Ethernet port 0. b. Ethernet input. C. External port 0. D. Exit port 0.
A. Ethernet port 0
What information is not included in an Ethernet frame? A. Frame size B. Source MAC address C. Pad D. Frame check sequence
A. Frame size
What are the key issues to be obtained from conducting a site survey for each of the following? A. Indoor B. Outdoor
A. Indoor -Electrical power -Wired network connection point(s) -Access point placement -RF coverage - user mobility -Bandwidth supported -Identify any significant RF interference B. Outdoor -Electrical poiwer (base access points) -Connection back to the home network -Antenna selection -Bandwidth supported -RF coverage -Any significant RF interference
An IP address for a computer is assigned by the A. Internet Assigned Number Authority B. local network admin C. users of the computer D. Internet Address Numbers Authority
A. Internet Assigned Number Authority (IANA)
The patch cable from a computer typically terminates into which of the following? A. Jack in a wall plate B. BNC connector C. Thinnet D. RJ-11 Modular plug E. RG-59
A. Jack in a wall plate
Dynamic assignment on a switch implies which of the following? (Select all that apply.) A. MAC addresses are assigned to a port when a host is connected. B. IP addresses are assigned to a port when a host is connected. C. MAC addresses are assigned to a switch when a host is connected. D. IP addresses are assigned to a switch when a host is connected.
A. MAC addresses are assigned to a port when a host is connected.
The network adminstrator is setting up a wireless network. There is a chance of radio interference. How can the network administrator avoid or minimize potential interference problems. A. Perform an RF study prior to installation of the wireless network. B. Contact all owners of equipment that may cause interference and ask them to use different systems. C. Contact the FCC to have the interferring sources shut down. D. All of these answers are correct.
A. Perform an RF study prior to installation of the wirless netowrk.
The connection to the router's console input is typically which of the following? (Select all that apply.) A. RS-232 B. RJ-45 C. DB9 D. RJ-11
A. RS-232 B. RJ-45
By convention, what is the name of the serial port 0 on a router? A. S0 B. System 0 C. Serial interface 0 D. Serial AUI 0
A. S0
Which of the following is used in wireless LANs to identify whether a client is to become a member of the wireless network? A. SSID B. MAC address C. IP address D. Echo
A. SSID
Which of the following are the three packets exchanged at the beginning of a TCP connection between two ports? A. SYN, SYN ACK, ACK B. SYN, SYN, ACK C. SYNC, ACK, ACK D. TCP does not use SYN packets.
A. SYN, SYN ACK, ACK
What router interface is most commonly used to interconnect LANs in a campus network? A. Serial B. Console port C. Ethernet D. ATM
A. Serial
Horizontal cabling consists of which of the following basic blocks? (Select two.) A. Switch or Hub B. Routers C. Backbone cabling D. Patch Panel
A. Switch or Hub D. Patch Panel
A UTP certification report lists the following Pairs 12 36 45 78 Length !310 308 ! 311 307 What do these results indicate? A. The cable fails the certification test. B. Pairs 3-6 and 7-8 will be certified. C Pairs 1-2 and 4-5 will be certified. D. The cable has passed the certification test. E. The ! sign indicates that the cable pair meets or exceeds power sum test criteria.
A. The cable fails the certification test.
Which of the following best defines aging time? A. The length of time a MAC address remains assigned to a port. B. The length of time an IP address remains assigned to a port. C. The length of time a MAC address remains assigned to a hub. D. The length of time an IP address remains assigned to a hub.
A. The length of time a MAC address remains assigned to a port.
A data problem is reported to the network administrator. The problem is found to be with the UTP network connection. What steps could the network administrator have taken to isolate the problem? (Select two.) A. Visually inspect all UTP terminations. B. Run a cable test using a cable tester. C. Use the ping command to verify the connection. D. Use pairs 4-5 and 7-8 to repair the connection. E. Contact the installer of the UTP cable to obtain a certification report.
A. Visually inspect all UTP terminations. C. Use the ping command to verify the connection.
The broadening of a pulse due to propagation of the spectral components of the light puse is called A. chromatic dispersion B. model dispersion C. polarization dispersion D. diffusion
A. chromatic dispersion
What is the most common network topology today? A. Star B. Hub C. Ring D. Mesh
A.Star
What is the Equipment Room (Structured Cabling System)?
AKA "ER", Room that houses electronic equipment such as servers and telephone equipment.
How does a layer 3 switch differ from a layer 2 switch?
AKA Multilayer switch, uses IP address (not just MAC addresses) to forward packets to their destination.
What does an "X" on the input to a hub represent?
AKA Uplink, indicating cross-connected inputs
What is a VLAN?
AKA Virtual LAN - A group of host computers and servers that are configured as if they are in the same LAN even i fthey reside across routers in separate LANs.
What command is used on a computer to view the contents of the ARP cache?
ARP = Address Resolution Protocol arp -a
What data traffic is sent across a network when a computer pings another computer and a hub is used to interconnect the computers?
ARP request, ARP reply, Ping echo and echo replies.
Define alien crosstalk.
AXT - Alient Cross Talk is unwanted signal coupling from one permanent link to another.
AUP
Acceptable Use Policy
ACL
Access Control List
AP
Access Point
channel service unit/data service unit (CSU/DSU)
Acts as a digital modem that terminates a digital circuit (for example, a T1 or an E1 circuit).
honey pot
Acts as a distracter. Specifically, a system designated as a honey pot appears to be an attractive attack target. One school of thought on the use of a honey pot is to place one or more honey-pot systems in a network to entice attackers into thinking the system is real. The attackers then use their resources attacking the honey pot, resulting in their leaving the real servers alone.
ARP
Address Resolution Protocol
Application layer (TCP/IP stack)
Addresses concepts described by Layers 5, 6, and 7 (that is, the session, presentation, and application layers) of the OSI model.
AES
Advanced Encryption Standard
APT
Advanced Persistent Tool
What is a UTP full channel test?
All the link elements from the wall plate to the hub or switch = full channel
virtual server
Allows a single physical server to host multiple virtual instances of various operating systems. This allows, for example, a single physical server to simultaneously host multiple Microsoft Windows servers and multiple Linux servers.
single sign-on (SSO)
Allows a user to authenticate once to gain access to multiple systems, without requiring the user to independently authenticate with each system.
peer-to-peer network
Allows interconnected devices (for example, PCs) to share their resources with one another. These resources could be, for example, files or printers.
Network Address Translation (NAT)
Allows private IP addresses (as defined in RFC 1918) to be translated into Internet-routable IP addresses (public IP addresses).
route redistribution
Allows routes learned by one routing protocol to be injected into the routing process of another routing protocol.
frequency-hopping spread spectrum (FHSS)
Allows the participants in a communication to hop between predetermined frequencies. Security is enhanced because the participants can predict the next frequency to be used but a third party cannot easily predict the next frequency. FHSS can also provision extra bandwidth by simultaneously using more than one frequency.
client-to-site VPN
Also known as a remote-access VPN, a client-to-site VPN interconnects a remote user with a site, as an alternative to dial-up or ISDN connectivity, at a reduced cost.
coaxial cable
Also known as coax, a coaxial cable is composed of two conductors. One of the conductors is an inner insulated conductor. This inner conductor is surrounded by another conductor. This second conductor is sometimes made of a metallic foil or woven wire.
Demark
Also known as demarcation point or a demarc extension, this is the point in a telephone network where the maintenance responsibility passes from a telephone company to a subscriber (unless the subscriber purchased an inside wiring plan). This demarc is typically a box mounted to the outside of a customer's building (for example, a residence).
TCP/IP stack
Also known as the DoD model, this four-layer model (as opposed to the seven-layer OSI model) targets the suite of TCP/IP protocols.
Marking
Alters bits within a frame, cell, or packet to indicate how a network should treat that traffic. Marking alone does not change how a network treats a packet. Other tools (such as queuing tools) can, however, reference markings and make decisions (for example, forwarding decisions or dropping decisions) based on those markings.
APT (Advanced Persistent Tool)
Although CompTIA uses Tool, most use Threat as the last word of the acronym. In either case, it is an unauthorized person in a network, undetected, for an exceedingly long period of time.
ARIN
American Registry for Internet Numbers
What is a piconet?
An Ad Hoc network of up to eight Bluetooth devices.
E1
An E1 circuit contains 32 channels, in contrast to the 24 channels on a T1 circuit. Only 30 of those 32 channels, however, can transmit data (or voice or video). Specifically, the first of those 32 channels is reserved for framing and synchronization, and the 17th channel is reserved for signaling (that is, to set up, maintain, and tear down a session).
Hub
An Ethernet hub is an older technology used to interconnect network components, such as clients and servers. Hubs vary in their number of available ports. A hub does not perform any inspection of the traffic it passes. Rather, a hub simply receives traffic in a port and repeats that traffic out all of its other ports.
What does Fast Ethernet describe?
An Ethernet system operating at 100Mbps
FTP bounce
An FTP bounce attack uses the FTP PORT command to covertly open a connection with a remote system. Specifically, an attacker connects to an FTP server and uses the PORT command to cause the FTP server to open a communications channel with the intended victim, which might allow a connection from the FTP server, while a connection directly from the attacker might be denied.
1000BaseT
An IEEE 802.3ab standard that specifies Gigabit Ethernet over Category 5 or better UTP cable. The standard allows for full-duplex transmission using four pairs of twisted cable up to 100 meters.
Authentication Header (AH)
An IPsec protocol that provides authentication and integrity services. however, it does not provide encryption services.
Encapsulating Security Payload (ESP)
An IPsec protocol that provides authentication, integrity, and encryption services.
Explain how a host knows whether a data packet was not received.
An acknowledgement packet is sent
A Record
An address record. This refers to one of three machines typically: the host sending data, the host receiving data, or an intermediary between the two (the next hop).
security association (SA)
An agreement between the two IPsec peers about the cryptographic parameters to be used in an ISAKMP session.
Anycast
An anycast communication flow is a one-to-nearest (from the perspective of a router's routing table) flow.
uninterruptible power supply (UPS)
An appliance that provides power to networking equipment in the event of a power outage.
What is Main Cross-connect (MC) (Structured Cabling System)?
An area that usually connects two or more buildings and is typically the central telecommunications connection point for a campus or building. AKA - Main Distribution Frame (MDF) AKA - Main Equipment Room AKA - Campus Distributor (CD)
electromagnetic interference (EMI)
An electromagnetic waveform that can be received by network cable (possibly corrupting data traveling on the cable) or radiated from a network cable (possibly interfering with data traveling on another cable).
Advanced Encryption Standard (AES)
An encryption algorithm for securing sensitive networks used by U.S. government agencies. Has become the encryption standard for corporate networks. Released in 2001, AES is typically considered the preferred symmetric encryption algorithm. AES is available in 128-bit key, 192-bit key, and 256-bit key versions.
What is an "ad hoc" network?
An independent network, clients communication directly w/ each other.
ASIC (application-specific integrated circuit)
An integrated circuit designed for a particular use instead of for general-purpose uses.
wide-area network (WAN) link
An interconnection between two devices in a WAN.
campus-area network (CAN)
An interconnection of networks located in nearby buildings (for example, buildings on a college campus).
Point-to-Point Tunneling Protocol (PPTP)
An older VPN protocol (that supported the dial-up networking feature in older versions of Microsoft Windows). Like L2TP and L2F, PPTP lacks native security features. However, Microsoft's versions of PPTP bundled with various versions of Microsoft Windows were enhanced to offer security features.
Common Address Redundancy Protocol (CARP)
An open standard variant of HSRP, which provides first-hop router redundancy.
Interior Gateway Protocol (IGP)
An routing protocol that operates within an autonomous system, which is a network under a single administrative control. OSPF and EIGRP are popular examples of IGPs.
APC
Angle Polished Connector
Multiport Repeater
Another name for a hub
Which layer of the TCP/IP model processes requests from hosts to ensure that a connection is made to the appropriate port?
Application Layer (top level)
ASP
Application Service Provider
ASIC
Application Specific Integrated Circuit
application-level firewall
Application-layer firewalls operate at the application layer of the OSI model. Application layer firewalls can inspect data packets traveling to or from an application.
data link layer
As Layer 2 of the OSI model, this layer is concerned with the packaging of data into frames and transmitting those frames on a network, performing error detection/correction, uniquely identifying network devices with an address, and handling flow control.
transport layer (OSI model)
As Layer 4 of the OSI model, it acts as a dividing line between the upper layers and lower layers. Specifically, messages are taken from the upper layers (Layers 5[nd]7) and encapsulated into segments for transmission to the lower layers (Layers 1[nd]3). Similarly, data streams coming from lower layers are decapsulated and sent to Layer 5 (the session layer) or some other upper layer, depending on the protocol.
session layer
As Layer 5 of the OSI model, it's responsible for setting up, maintaining, and tearing down sessions.
link aggregation
As defined by the IEEE 802.3ad standard, link aggregation allows multiple physical connections to be logically bundled into a single logical connection.
differentiated services (DiffServ)
As its name suggests, DiffServ differentiates between multiple traffic flows. Specifically, packets are marked, and routers and switches can then make decisions (for example, dropping or forwarding decisions) based on those markings.
Server
As its name suggests, a server serves up resources to a network. These resources might include e-mail access as provided by an e-mail server, web pages as provided by a web server, or files available on a file server.
Asset management
As related to networks, this is a formalized system of tracking network components and managing the lifecycle of those components.
ADSL
Asymmetric Digital Subscriber Line
ATM
Asynchronous Transfer Mode
ATM
Asynchronous Transfer Mode - Layer 2 WAN tech uses fixed-length cells as its protocol data unit
wireless router
Attaches to a wired network and provides access to that wired network for wirelessly attached clients, like a wireless AP. However, a wireless router is configured such that the wired interface that connects to the rest of the network (or to the Internet) is on a different IP network than the wireless clients. Typically, a wireless router performs NATing between these two IP address spaces.
cable modem
Attaches to the same coaxial cable (typically in a residence) that provides television programming. A cable modem can use predetermined frequency ranges to transmit and receive data over that coaxial cable.
social engineering
Attackers sometimes use social techniques (which often leverage people's desire to be helpful) to obtain confidential information. For example, an attacker might pose as a member of an IT department and ask a company employ for their login credentials in order for the "IT staff to test the connection." This type of attack is called social engineering.
What are the two key distance-limiting parameters in fiber-optic transmissions?
Attenuation & dispersion
AAA
Authentication Authorization and Accounting
AH
Authentication Header
AAAA
Authentication, Authorization, Accounting and Auditing
AAAA
Authentication, Authorization, Accounting and Auditing
AAAA
Authentication, authorization, accounting, and auditing. Authentication is the process to determine whether someone is authorized to use the network—if the person can log on to the network. Authorization refers to identifying the resources a user can access after the user is authenticated. Accounting refers to the tracking methods used to identify who uses the network and what they do on the network. Auditing refers to the ability to associate actions with the machine/user in question.
AAA
Authentication, authorization, and accounting. Authentication is the process to determine whether someone is authorized to use the network—if the person can log on to the network. Authorization refers to identifying the resources a user can access after the user is authenticated. Accounting refers to the tracking methods used to identify who uses the network and what they do on the network.
APIPA
Automatic Private Internet Protocol Addressing
AS
Autonomous System
What is the overall length limitation of a UTP cable run from the telecommunications closet to a networking device in tthe work area? A. 10 meters B. 100 meters C. 10K meters D. 100K meters
B. 100 meters
Which of the following are current wireless networking standards (select all that apply.) A. 802.12n B. 802.11g C. 803.11g D. 802.11a E. 802.11b F. 802.55a G. 802.11n H. 802.1a i. 802.11ac
B. 802.11g D. 802.11a E. 802.11b G. 802.11n I. 802.11ac
Which of the following is a disadvantage of the auto-negotiation protocol? A. It is useful only in LANs that have multiple connection capabilities. B. A failed negotiation on a functioning link can cause a link failure. C. It's recommended for use in critical network data paths. D. It works at 10Mbps.
B. A failed negotiation on a functionnig link can cause a link failure.
What is the benefit of shielded twisted-pair cable? A. Ease of installation B. Excellent EMI protection C. Less expensive D. Preferrred by the industry for all installations E. None of these answers is correct.
B. Excellent EMI Protection
What is the name of the optical-to-fiber interface used at 1Gbps? A. XENPAK B. GBIC C. 10GBIC D. ZENPAK
B. GBIC
Which of the following best characterizes CSMA/CA? A. It replaces CSMA/CD B. It provides carrier sense with collision avoidance. C. It provides carrier sense with congestion avoidance. D. It provides congestion sensing wiht collision avoidance.
B. It provides carrier sense with collision avoidance.
Which of the following is another name for a switch? A. Multiport repeater B. Multiport bridge C. Multiport router D. Multiport hub
B. Multiport bridge
Which of the following are advantages of using a bridge to interconnect LANs? A. Works best in low-traffic areas B. Relatively inexpensive C. Can be used to route data traffic D. Easy to install E. Reduces collision domains
B. Relatively inexpensive D. Easy to install
What is the purpose of the Secure tab on a switch? A. The switch port will use port discovery to assign a MAC address to the port. B. The switch port will automatically disable itself if a device with a different MAC address connects to the port. C. The switch port will use a different MAC address than the one connected to the port. D. This enables the switch to select what networking devices have a selectable IP address.
B. The switch port will automatically disable itself if a device with a different MAC address connects to the port.
An Ethernet packet size greater than 1500 bytes is called A. a bad frame B. a jumbo frame C. an MTU D. All of the above E. None of the above
B. a jumbo frame
The pad field in an Ethernet packet A. is used to bring the total number of bytes up to 46 if the data field is less than 46 bytes B. is used to bring the total number of bytes up to 64 if the data field is less than 64 bytes. C. is not required with CSMA/CD D. provides grouping of the information for transmission.
B. is used to bring the total number of bytes up to 64 if the data field is less than 64 bytes
BRI
Basic Rate Interface
BSSID
Basic Service Set Identifier
BERT
Bit-Error Rate Test
borrowed bits
Bits added to a classful subnet mask.
What values are used when configuring HyperTerminal for connecting to a router's console port?
Bits per second 9600 Data bits 8 Parity None Stop bits 1 Flow Control None
BLE
Bluetooth Low Energy
BootP
Boot Protocol/Bootstrap Protocol
BGP
Border Gateway Patrol - Exterior Gateway Protocol that routes based on number of autonomous system hops to reach destination
BGP
Border Gateway Protocol
What is another term for Network Congestion?
Bottlenecking
BPDU
Bridge Protocol Data Unit
BYOD
Bring Your Own Device
BNC
British Naval Connector/Bayonet Niell-Concelman
The link for a switch connection is isolated from other data traffic except for what type of messages?
Broadcast or Multicast messages. Broadcast is sent to all devices connected to the LAN. Multicast messages are sent to a specific group of hosts on the network.
What term is used for excessive broadcasts on a network?
Broadcast storm
Define "dispersion".
Broadening of a light pulse as it propagates through a fiber strand.
BCP
Business Continuity Plan
How does an access point know if a wireless data packet is intended for its network?
By the SSID
How many pins does an RJ-45 modular plug have? A. 4 B. 6 C. 8 D. 16 E. None of these answers is correct
C. 8 Pins
What is the data rate of OC-192? A. 1.522Mbps B. 155.52Mbps C. 9.95Gbps D. 2.488Gbps
C. 9.95Gbps
The IP address 10.10.20.250 is an example of which of the following? (Select ALL that apply) A. A class A address B. A Class B address C. A private IP address D. A routable IP address E. A nonroutable Internet IP address
C. A private IP address E. A nonroutable Internet IP address
The home IP address for a network is assigned by which of the following? A. ARIN, the Association of Registered Internet Numbers B. ARIN, the American Registry for Internet Names C. ARIN, the American Registry for Internet Numbers D. ARNN, the American Registry for Internet Names and Numbers
C. ARIN, The American Registry for Internet Numbers
What is the length of time an IP address is assigned to a switch port called? A. Delay time B. Enable time C. Aging time D. Access time
C. Aging time
What is RJ-45 a. A 45 pin connector for CAT6 b. An IEEE standard for data speed c. An 8-pin modular connector for twisted-pair Ethernet d. A protocol used to verify a communications link
C. An 8-pin modular connector for twisted-pair Ethernet
What is an 8P8C connector? A. Another term for an RJ-11 connector B. Another term for an RJ-6 connector C. Another term for an RJ-45 connector D. Another term for an RS-232
C. Another term for an RJ-45 connector
In which switch mode is a data packet forwarded to the destination as soon as the MAC address has been read? A. Store-and-forward B. Adaptive fast-forward C. Cut-through D. Fast-forward
C. Cut-through
Which of the following is true of an intranet? (Select ALL that apply.) A. It uses Class E addressing B. It is used in high-speed (Gigabit) Ethernet C. It is an internal network that provides files and resource sharing. D It enables Fast Ethernet connections. E. It is not accessed from the Internet.
C. It is an internal network that provides files and resource sharing. E. It is not accessed from the Internet
Which of the following is true of Wi-Fi? A. The Wi-Fi Alliance is an organization that assembles and tests wireless equipment before it is shipped to vendors. B. The Wi-Fi Alliance is an organization that tests and certifies wireless equipment for compliancewith the 803.1 standards. C. The Wi-Fi Alliance is an organization that tests and certifies wireless equipment for compliance with the 802.11x standards. D. None of these answers is correct.
C. The Wi-Fi Alliance is an organization that tests and certifies wireless equipment for compliance with the 802.11x standards.
Serial interfaces on a router are typically used for which of the following? A. To interconnect routers B. To interconnect hubs C. To connect to commmunication carriers D. To connect to auxiliary ports
C. To connect to communication carriers.
The length difference in the wire pairs for UTP A. indicates that the cable should not be certfied B. indicates that the cable should be certified C. is due to the difference in the cable twists for each wire. D. is due to poorly manufactured cables.
C. is due to the difference in the cable twists for each wire.
The broadening of a puse due to the different path lengths taken through the fiber by different modes is called A. chromatic dispersion B. polarization mode dispersion C. modal dispersion D. diffusion
C. modal dispersion
What is the difference between CAT5 and CAT5e?
CAT5 has a data rate of 100Mbps and CAT5e has a data rate of 1000Mbps (Gigabit Ethernet) using all 4 wire pairs supporting full-duplex
What networking protocol does Ethernet use?
CSMA/CD - Carrier Sense Multiple Access / Collision Detection
A NEXT measurement of 59.5dB is made on wire pairs 1-2 and 3-6. A measurement of 51.8 is made on wire pairs 3-6 and 7-8. Which cable pairs have the best measured NEXT performance?
Cable with the measurement 59.5 dB
What is Horizontal Cabling (Structured Cabling System)?
Cabling that extends out form the Telecommunications Closet into the LAN work area.
What is Backbone Cabling (Structured Cabling System)?
Cabling that interconnects Telecommunications Closets, Equipment Rooms (ER), and Cabling Entrances in the same building and between buildings.
CAN
Campus Area Network
route command
Can add, modify, or delete routes in the IP routing table of Microsoft Windows and UNIX hosts. In addition, the route command can be used to view the IP routing table of Microsoft Windows hosts.
arp command
Can be used in either the Microsoft Windows or UNIX environment to see what a Layer 2 MAC address corresponds to a Layer 3 IP address.
content switch
Can be used to load balance requests for content across a group of servers containing that content. If one of the servers in the group needed to have maintenance performed, that server could be administratively removed from the group, as defined on the content switch. As a result, the content switch can help maximize up time when performing server maintenance. It minimizes the load on individual servers by distributing its load across multiple identical servers. A content switch also allows a network to scale because one or more additional servers could be added to the server group defined on the content switch if the load on existing servers increases.
netstat command
Can display a variety of information about IP-based connections on a Windows or UNIX host.
nslookup command
Can resolve a FQDN to an IP address on Microsoft Windows
dig command
Can resolve a FQDN to an IP address on UNIX hosts.
host command
Can resolve a FQDN to an IP address on hosts.
hold-down timers
Can speed the convergence process of a routing protocol. After a router makes a change to a route entry, the hold-down timer prevents any subsequent updates for a specified period of time. This approach can help stop flapping routes (which are routes that oscillate between being available and unavailable) from preventing convergence.
CNAME
Canonical Name
Expand the acronym CSMA/CD. What protocol uses CSMA/CD?
Carrier Sense Multiple Access with Collision Detection - The networking protocol Ethernet
CSMA/CA
Carrier Sense Multiple Access/Collision Avoidance
CSMA/CD
Carrier Sense Multiple Access/Collision Detection
10BASE-T
Cat 3 UTP - 10Mbps, 100 m
100BASE-TX
Cat 5 UTP - 100Mbps, 100 m
1000BASE-T
Cat 5e UTP - 1Gbps, 100 m
1000BASE-TX
Cat 6 UTP - 1Gbps, 100 m
10GBASE-T
Cat 6a or Cat 7 - 10Gbps, 100 m
CAT
Category
CPU
Central Processing Unit
CHAP
Challenge Handshake Authentication Protocol
CRAM-MD5
Challenge-Response Authentication Mechanism-Message Digest 5
CRAM-MD5
Challenge-Response Authentication Mechanism - Message Digest 5
List 5 steps that can be used to protect a home network.
Change the default factory passwords, Change the default SSID, Turn on encryption, Turn off SSID broadcast, and Enable MAC address filtering.
CSU
Channel Service Unit
Layer 6 - Presentation Layer
Character encoding, application encryption, often combined w/ application layer (SSL/TLS)
CoS
Class of Service
classification
Classification is the process of placing traffic into different categories.
CIDR
Classless Inter-Domain Routing
CCTV
Closed Circuit TV
CASB
Cloud Access Security Broker
10BASE5
Coax (thicknet) - 10Mbps, 500 m
10BASE2
Coax (thinnet) - 10Mbps, 185 m
RG-58
Coax - 50 Ohms - short distance
RG-6
Coax - 75 Ohms - long distance
RG-59
Coax - 75 Ohms - short distance
F-connector
Coaxial - tv connections
BNC
Coaxial - with pin
CDMA
Code Division Multiple Access
CVW
Collaborative Virtual Workspace
CARP
Common Address Redundancy Protocol
Open Systems Interconnection (OSI) reference model
Commonly referred to as the OSI model or the OSI stack. This seven-layer model categorizes various network technologies.
Point-to-Point Protocol over Ethernet (PPPoE)
Commonly used between a DSL modem in a home (or business) and a service provider. Specifically, PPPoE encapsulates PPP frames within Ethernet frames. PPP is used to leverage its features, such as authentication.
CaaS
Communication as a Service
Layer 5 - Session Layer
Communication management, control protocols, tunneling protocols
CAM
Content Addressable Memory
List 2 advantages of wireless networking.
Cost and mobility
CWDM
Course Wave Division Multiplexing
CE
Customer Edge - router that provides connectivity between network and server provider (don't run MPLS)
CPE
Customer Premises Equipment - device resides at customer site (connects w/ MPLS service provider)
CRC
Cyclic Redundancy Checking
What is the equivalent hexadecimal number for 13?
D
What is the "two-deep" rule relative to optical networking? A. The horizontal distribution to the work floor can have only two 8P8C connections. B. The horizontal distribution to the work floor can only have two ST connetions to the fiber patch panel. C. This is no longer an issue with high-speed single-mode fiber and wave division multiplexing equipment. D. A building should have only the main distribution and the intermediate distribution that feeds the horizontal distribution to the work area.
D. A building should have only the main distribution and the intermediate distribution that feeds the horizontal distribution to the work area.
What does AUI stand for? A. Auxiliary unit input B. Attachment unit interconnected C. Auxiliary unit interface D. Attachment unit interface
D. Attachment unit interface
What type of cable is currently recommended for LAN work areas? A. STP B. CAT6 STP C. CAT 5e UTP D. CAT6 UTP E. CAT7 UTP
D. CAT6 UTP
What is the material surrounding the core of an optical waveguide called? A. Aperture B. Mode field C. Step-index D. Cladding E. Graded-index
D. Cladding
The AUI port on a router connects to which networking protocol? A. 100BASE-T B. 10BASE-T C. Token Ring D. Ethernet
D. Ethernet
Define MIMO relative to 802.11n. A. MIMO is a multiplexing technique in which the power is split into multiple parts called spatial currents. B. MIMO is frequency-division multiplexing technique in which the data stream is split into multiple parts called spectral streams. C. MIMO is an OFDM multiplexing technique in which the data stream is split into multiple parts called spatial streams. D. MIMO is a space-division multiplexing technique in which the data stream is split into multiple parts called spectral streams.
D. MIMO is a space-division multiplexing technique in which the data stream is split into multiple parts called spectral streams.
Permanent networking cabling within a building belongs to A. vertical cabling B. the work area C. the equipment room D. None of these answers is correct.
D. None of these answers is correct - Correct answer is horizontal cabling
The physical connection where a router connects to the network is called the A. router port. B. network port. C. network interface. D. router interface.
D. Router interface
Which of the following terms is used for a MAC address being manually assigned? A. Dynamic assignment B. ARP assignment C. DHCP assignment D. Static assignment
D. Static assignment
Which of the following best defines store-and-forward relative to switch operation? A. The frame is stored in CAM and then forwarded to the source for confirmation. B. The frame is stored in CAM and then forwarded to the destination for confirmation. C. The header is received before being forwarded to the destination. D. The entire frame is received before a decision is made regarding forwarding to its destination.
D. The entire frame is received before a decision is made regarding forwarding ot its destination.
What does the term "last mile" mean, relative to telecommunications? A. The distance from the RF transmiter ot the receiver in WiMAX. B. A measurement of signal coverage for WiMAX and for Wi-Fi. C. A term for the last connection prior to linking ot the RF transmitter. D. The last part of the connection from the telecommunications provider to the customer.
D. The last part of the connection from the telecommunications provider to the customer.
A disadvantage of the token-ring system is that if an error changes the token patter, it can cause the toke to stop circulating. This can be elimated by adding which of the following? A. Router B. Multiport Repeater C. Token Passer D. Token-ring hub
D. Token-ring hub
The broadening of a light pulse due to the different propagation velocities of the X and Y polarization components of the light pulse is called A. modal dispersion B. chromatic dispersion C. diffusion D. polarization mode dispersion
D. polarization mode dispersion
Routing tables on a router keep track of A. port assignments. B. MAC address assignments C. gateway address of LANs D. routes to use for forwarding data to its destination
D. routes to use for forwarding data to its destination
DLC
Data Link Control
DLP
Data Loss Prevention
DSU
Data Service Unit
What is meant by the term wire-speed routing?
Data packets are processed as quickly as they arrive. Possible because the processing time of layer 3 switches can be as fast as the input data rate.
Name six issues that should be considered when planning a home network.
Data speed, cost, ease of implementation, appearance, home access, and public access
DOCSIS
Data-Over-Cable Service Interface Specification
dB
Decibel
What are the potential problems related to using default factory passwords?
Default settings are known to the public, including those that would try to gain access to your network.
Spanning Tree Protocol (STP)
Defined by the IEEE 802.1D standard, it allows a network to have redundant Layer 2 connections, while logical preventing a loop, which could lead to symptoms such as broadcast storms and MAC address table corruption.
Power over Ethernet (PoE)
Defined by the IEEE 802.3af and 802.3at standards, PoE allows an Ethernet switch to provide power to an attached device (for example, a wireless access point, security camera, or IP phone), by applying power to the same wires in a UTP cable that are used to transmit and receive data.
ad hoc topology
Defines a wireless network layout whereby devices communicate directly among themselves without using an access point. Sometimes called an unmanaged or peer-to-peer wireless topology.
Client
Defines the device an end-user uses to access a network. This device might be a workstation, laptop, smartphone with wireless capabilities, a tablet, or a variety of other end-user terminal devices.
DMZ
Demilitarized Zone
DoS
Denial of Service
DWDM
Dense Wavelength Division Multiplexing
What is an "association", and what is its purpose?
Describes a wireless connection made. AP uses associations to build a table of users on the wireless network.
DR
Designated Router
Daas
Desktop as a Service
DNAT
Destination Network Address Translation
time domain reflectometer (TDR)
Detects the location of a fault in a copper cable by sending an electric signal down the copper cable and measuring the time required for the signal to bounce back from the cable fault. A TDM can then mathematically calculate the location of the fault.
optical time domain reflectometer (OTDR)
Detects the location of a fault in a fiber cable by sending light down the fiber-optic cable and measuring the time required for the light to bounce back from the cable fault. The OTDM can then mathematically calculate the location of the fault.
DLR
Device Level Ring
Media
Devices need to be interconnected via some sort of media. This media could be copper cabling. Alternatively, it could be a fiber-optic cable. Media might not even be a cable, as is the case with wireless networks, where radio waves travel through the media of air.
What is the difference between T568A and T568B?
Different wiring guidlines (color map). 2 different manufacturer standards used to wire the modular connector hardware. Industry favors T568A wiring order.
DSCP
Differentiated Services Code Point
DSL
Digital Subscriber Line
DSSS
Direct Sequence Spread Spectrum
DSSS
Direct-sequence spread spectrum - modulates data over entire range of frequencies w/ chips including random data
full-mesh topology
Directly connects every site to every other site.
nbtstat command
Displays NetBIOS information for IP-based networks. The nbt prefix of the nbtstat command refers to NetBIOS over TCP/IP, which is called NBT (or NetBT). This command can, for example, display a listing of NetBIOS device names learned by a Microsoft Windows-based PC.
DCS
Distributed Computer System
DDoS
Distributed Denial of Service
DNS
Domain Name Service/Domain Name Server/ Domain Name System
DNS
Domain Name Service/Domain Name Server/Domain Name System
An IPv4 address is typically expressed in what format?
Dotted decimal
DHCP
Dynamic Host Configuration Protocol
DNAT/SNAT
Dynamic NAT/Static NAT - auto assign/statically assign inside global address
Dynamic Host Configuration Protocol (DHCP)
Dynamically assigns IP address information (for example, IP address, subnet mask, DNS server's IP address, and default gateway's IP address) to network devices.
E1
E-Carrier Level 1
What do EIA and TIA stand for?
EIA = Electronics Industries Alliance TIA = Telecommunications Industry Association
What is the benefit of using shielded twisted-pair cabling?
EMI protection
The telco and the ISP usually connect to what room in the campus network hierarchy?
ER - Equipment Room
Why do entries into the bridge table have a limited lifetime?
Each MAC address entry into the bridging table remains active as long as there is periodic data traffic activity. The entries expire so that the table only lists the MAC address for the networking devices recently active in the network.
ELSR
Edge Label Switch Router - on edge of MPLS server providers' cloud and interconnects w/ one or more customers
EMI
Electromagnetic Interference
Expand and describe EMI.
Electromagnetic Interference - Originates from devices such as motors, power lines and from some lighting devices, such as fluorescent lights.
EIA/TIA
Electronic Industries Alliance/ Telecommunication Industries Association
EIA/TIA
Electronic Industries Alliance/Telecommunication Industries Association
ESD
Electrostatic Discharge
ESP
Encapsulated Security Payload
Bit-Error Rate Tester
Equipment used to test interference on a transmission medium, faulty cabling, that can cause errors in transmission of bits
RJ-45
Ethernet - 8-pin connector
Ethernet
Ethernet is a Layer 1 technology developed by Xerox and encompasses a variety of standards, which specify various media types, speeds, and distance limitations.
XDSL
Extended Digital Subscriber Line
ESSID
Extended Service Set Identifier
EUI
Extended Unique Identifier
EAP
Extensible Authentication Protocol
EDNS
Extension Mechanisms for DNS
EGP
Exterior Gateway Protocol
EIGRP
Exterior-Interior Gateway Routing Protocol - (Cisco proprietary) route based on bandwidth and delay w/ possible additional parameters
Define a "pseudorandom sequence" as it applies to FHSS.
FHSS - Frequency-hopping spread spectrum Pseudorandom sequence is a sequence appears random but repeats itself. FHSS requires the transmitting and receiving units to know the hopping sequence to synchronize.
Expand the following acryonyms: A. FTTC B. FTTH C. FTTB D. FTTD
FTTC - Fiber-to-the-curb FTTH - Fiber-to-the-home FTTB - Fiber-to-the-business FTTD - Fiber-to-the-desktop
True or False: If the signal quality drops from excellent to good, the antenna or access point should be replaced.
False - move to a different height.
A NEXT measurement of 59.5 dB is made on wire pairs 1-2 and 3-6, A NEXT measure of 51.8 dB is made on wire pairs 3-6 and 7-8. True or false: Pairs 3-6 and 7-8 have the best NEXT performance measurement?
False.
True or false: A CAT5e/6 link test tests from one termination to another.
False.
True or false: Only two wire pairs are used to obtain a proper power sum measurement.
False.
True or false: The four layers of the TCP/IP model are application, network, Internet, and data link.
False: Application, Transport, Internet, Network Interface
Which switch mode offers minimum latency?
Fast-forward, a form of Cut-through switching. Received data packets are sent to the destination as soon as the destination MAC address is extracted.
What is a dispersion compensating fiber?
Fiber that acts as an equalizer, canceling dispersion effects and yielding close to zero dispersion in the 1550nm region
FC
Fibre Channel
FCoE
Fibre Channel over Ethernet
FTP
File Transfer Protocol
FTPS
File Transfer Protocol Security
What is F/UTP and what is its purpose?
Foil over twisted-pair cabling. To shield from EMI and add security (data doesn't radiate outside of cable)
FCS
Frame Check Sequence
FDM
Frequency Division Multiplexing
FHSS
Frequency Hopping Spread Spectrum
FM
Frequency Modulation
What is the frequency range used by 802.11a, and what modulation technique is used?
Frequency range of 802.11a = 5.180Ghz - 5.805Ghz, Modulation technique = OFDM, Orthogonal frequency-division multiplexing.
FHSS
Frequency-hopping spread spectrum - allows participants in a communication to hop between predetermined frequencies
FQDN
Fully Qualified Domain Name
GPG
GNU Privacy Guard
GLBP
Gateway Load Balancing Protocol
GRE
Generic Routing Encapsulation
GBIC
Gigabit Interface Converter
Gbps
Gigabits per second
GSM
Global System for Mobile Communications
HVAC
Heating, Ventilation and Air Conditioning
Hz
Hertz
HA
High Availability
HT
High Throughput
HDMI
High-Definition Multimedia Interface
HDLC
High-Level Data Link Control
HSPA
High-Speed Packet Access
Which subsystem does permanent networking cabling within a building belong to?
Horizontal cabling
HIDS
Host Intrusion Detection System
HIPS
Host Intrusion Prevention System
HSRP
Hot Standby Router Protocol
HTTP
Hypertext Transfer Protocol
HTTPS
Hypertext Transfer Protocol Secure
Which organization assigns IP address for North America?
IANA = Internet Assigned Numbers Authority
Which important networking troubleshooting tool is part of ICMP, and how does it test a network connection?
ICMP = Internet Control Message Protocol Ping - Uses a series of echo request and receives echo replies from networking devices. Ping = packet Internet groper
intrusion detection system (IDS)
IDS devices can recognize the signature of a well-known attack and respond to stop the attack. However, an IDS sensor does not reside in-line with the traffic flow. Therefore, one or more malicious packets might reach an intended victim before the traffic flow is stopped by an IDS sensor.
When is IGMP used?
IGMP = Internet Group Message Protocol is used when one host needs to send data to many destination hosts.
intrusion prevention system (IPS)
IPS devices can recognize the signature of a well-known attack and respond to stop the attack. An IPS device resides in-line with the traffic flow, unlike an IDS sensor.
What is the difference between "straight" and "cross-connected" input ports?
If a device has a cross-connected port, then a straight-through cable is used because the device is providing the alignment.
congestion avoidance
If an interface's output queue fills to capacity, newly arriving packet are discarded (or tail dropped). Congestion avoidance can prevent this behavior. RED is an example of a congestion-avoidance mechanism.
Warchalking
If an open WLAN (or a WLAN whose SSID and authentication credentials are known) is found in a public place, a user might write a symbol on a wall (or some other nearby structure) to let others know the characteristics of the discovered network. This practice, which is a variant of the decades-old practice of hobos leaving symbols as messages to fellow hobos, is called warchalking.
Why is delay skew critical?
If the wire lengths of different wire pairs are significantly different, then the data on one wire will take longer to propagate along the wire and arrive at the receiver at a different time and potentially create distortion of the data and data packet loss.
cable certifier
If you are working with existing cable and want to determine its category, or if you simply want to test the supported frequency range (and therefore data throughput) of the cable, you can use a cable certifier.
Why was OFDM selected for WiMAX?
Improved NLOS, non-line-of-sight characteristics.
B (bearer) channel
In ISDN, a 64 Kbps channel that carries data. See also D (delta) channel.
nondesignated port
In STP terms, nondesignated ports block traffic to create a loop-free topology.
designated port
In a STP topology, every network segment has a single designated port, which is the port on that segment that is closest to the root bridge, in terms of cost. Therefore, all ports on a root bridge are designated ports.
root port
In a STP topology, every nonroot bridge has a single root port, which is the port on that switch that is closest to the root bridge, in terms of cost.
client/server network
In a client/server network, a dedicated server (for example, a file server or a print server) provides shared access to a resource (for example, files or a printer). Clients (for example, PCs) on the network with appropriate privilege levels can gain access to those shared resources.
Supplicant
In a network using 802.1X user authentication, a supplicant is the device that wants to gain access to a network.
Authentication server
In a network using 802.1X user authentication, an authentication server typically, a RADIUS server) checks a supplicant's credentials. If the credentials are acceptable, the authentication server notifies the authenticator that the supplicant is allowed to communicate on a network. The authentication server also gives the authenticator a key that can be used to securely transmit data during the authenticator's session with the supplicant.
Authenticator
In a network using 802.1X user authentication, an authenticator forwards a supplicant's authentication request on to an authentication server. After the authentication server authenticates the supplicant, the authenticator receives a key that is used to communicate securely during a session with the supplicant.
ring topology
In a ring topology, traffic flows in a circular fashion around a closed network loop (that is, a ring). Typically, a ring topology sends data, in a single direction, to each connected device in turn, until the intended destination receives the data.
star topology
In a star topology, a network has a central point (for example, a switch) from which all attached devices radiate.
beaconing
In a wireless network, beaconing refers to the continuous transmission of small packets (beacons) that advertise the presence of a base station (access point).
Trunk
In the context of an Ethernet network, a trunk is a single physical or logical connection that simultaneously carries traffic for multiple VLANs. However, a trunk also refers to an interconnection between telephone switches, in the context of telephony.
T3
In the same T-carrier family of standards as a T1, a T3 circuit offers an increased bandwidth capacity. Although a T1 circuit combines 24 DS0s into a single physical connection to offer 1.544 Mbps of and width, a T3 circuit combines 672 DS0s into a single physical connection, with a resulting bandwidth capacity of 44.7 Mbps.
What improvements do CAT6 and CAT7 cable provide?
Increased bandwidth and data rate / 250Mhz & 10Gbps
ICA
Independent Computer Architecture
IT
Information Technology
IaaS
Infrastructure as a Service
IV
Initialization Vector
stateful firewall
Inspects traffic leaving the inside network as it goes out to the Internet. Then, when returning traffic from the same session (as identified by source and destination IP addresses and port numbers) attempts to enter the inside network, the stateful firewall permits that traffic. The process of inspecting traffic to identify unique sessions is called stateful inspection.
traffic shaping
Instead of making a minimum amount of bandwidth available for specific traffic types, you might want to limit available bandwidth. Both policing and shaping tools can accomplish this objective. Collectively, these tools are called traffic conditioners. Traffic shaping delays excess traffic by buffering it as opposed to dropping the excess traffic.
Policing
Instead of making a minimum amount of bandwidth available for specific traffic types, you might want to limit available bandwidth. Both policing and trafficshaping tools can accomplish this objective. Collectively, these tools are called traffic conditioners. Policing can drop exceeding traffic, as opposed to buffering it.
IEEE
Institute of Electrical and Electronics Engineers
IEEE (Expand and give definition/description)
Institute of Electrical and Electronics Engineers - One of the major standards-setting bodies for technological development
ISDN
Integrated Services Digital Network
ITS
Intelligent Transportation System
proxy server
Intercepts requests being sent from a client and forwards those request on to their intended destination. The proxy server then sends any return traffic to the client which initiated the session. This provides address hiding for the client. Also, some proxy servers conserve WAN bandwidth by offering a content caching function. In addition, some proxy servers offer URL filtering to, for example, block users from accessing social networking sites during working hours.
metropolitan-area network (MAN)
Interconnects locations scattered throughout a metropolitan area.
wide-area network (WAN)
Interconnects network components that are geographically separated.
local-area network (LAN)
Interconnects network components within a local region (for example, within a building).
site-to-site VPN
Interconnects two sites, as an alternative to a leased line, at a reduced cost.
IGP
Interior Gateway Protocol
IGRP
Interior Gateway Routing Protocol
IDF
Intermediate Distribution Frame
IS-IS
Intermediate System to Intermediate System
IS-IS
Intermediate System-to-Intermediate System - link-state route based on Dijkstra's shortest path first algorithm (configurable, dimensionless metric)
IANA
Internet Assigned Numbers Authority
ICS
Internet Connection Sharing/Industrial Control System
ICMP
Internet Control Message Protocol
ICANN
Internet Corporation for Assigned Names and Numbers
IGMP
Internet Group Management Protocol - defines which interfaces have multicast receivers attached
IGMP
Internet Group Message Protocol
IKE
Internet Key Exchange
IMAP4
Internet Message Access Protocol version 4
InterNIC
Internet Network Information Center
IP
Internet Protocol
IPSec
Internet Protocol Security
IPv4
Internet Protocol version 4
IPv6
Internet Protocol version 6
ISAKMP
Internet Security Association and Key Management Protocol
ISP
Internet Service Provider
IoT
Internet of Things
Expand ISATAP
Intra-site Automatic Tunnel Addressing Protocol
IDS
Intrusion Detection System
IPS
Intrusion Prevention System
carrier sense multiple access collision avoidance (CSMA/CA)
Just as CSMA/CD is needed for half-duplex Ethernet connections, CSMA/CA is needed for WLAN connections because of their half-duplex operation. Similar to how an Ethernet device listens to an Ethernet segment to determine whether a frame exists on the segment, a WLAN device listens for a transmission on a wireless channel to determine whether it is safe to transmit. In addition, the collision-avoidance part of the CSMA/CA algorithm causes wireless devices to wait for a random backoff time before transmitting.
Explain what data traffic is seen by computer 3 when computer 1 pings computer 2 in a LAN if a switch is used to interconnect the computers.
Just the ARP request (needs MAC address)
KVM
Keyboard Video Mouse
Kbps
Kilobits per second
LSR
Label Switch Router - part of service provider's MPLS cloud and makes frame-forwarding decisions
physical layer
Layer 1 of the OSI model, it is concerned with the transmission of bits on a network.
A network switch operates at which layer of the OSI model?
Layer 2
L2TP
Layer 2 Tunneling Protocol
network layer
Layer 3 of the OSI model, it is primarily concerned with forwarding data based on logical addresses.
presentation layer
Layer 6 of the OSI model, it is responsible for the formatting of data being exchanged and securing the data with encryption.
Application layer (OSI model)
Layer 7 of the OSI model, it provides application services to a network. An important, and an often-misunderstood concept, is that end-user applications do not reside at the application layer. Instead, the application layer supports services used by end-user applications. Another function of the application layer is advertising available services.
LED
Light Emitting Diode
LWAPP
Light Weight Access Point Protocol
What is Infrared Light?
Light extending from 680nm up to the wavelengths of microwaves.
What is the Optical Spectrum?
Light frequencies from the infrared on up.
LDAP
Lightweight Directory Access Protocol
Challenge Handshake Authentication Protocol (CHAP)
Like PAP, CHAP performs one-way authentication. However, authentication is performed through a three-way handshake (challenge, response, and acceptance messages) between a server and a client. The three-way handshake allows a client to be authenticated without sending credential information across a network.
multilayer switch
Like a router, a multilayer switch can make traffic forwarding decisions based on Layer 3 information. Although multilayer switches more closely approach wire-speed throughput that most routers, routers tend to have a greater feature set and are capable of supporting more interface types than a multilayer switch.
Switch
Like an Ethernet hub, an Ethernet switch interconnects network components. Like a hub, switches are available with a variety of port densities. However, unlike a hub, a switch doesn't simply take traffic in on one port and forward copies of that traffic out all other ports. Rather, a switch learns which devices reside off of which ports. As a result, when traffic comes in a switch port, the switch interrogates the traffic to see where it's destined. Then, based on what the switch has learned, the switch forwards the traffic out of the appropriate port, and not out all of the other ports.
LACP
Link Aggregation Control Protocol
LLDP
Link Layer Discovery Protocol
LSA
Link State Advertisements
What do the link lights on a hub indicate?
Link lights indicate whether the transmit and receive paris are properly aligned and connected devices are communicating. A way to verify the network connection.
Expand the acronym LAN
Local Area Network
LAN
Local Area Network
LAN (Expand and give definition/description)
Local Area Network - A network of users who share computer resources in a limited area
LC
Local Connector
LEC
Local Exchange Carrier
What is the Telecommunications Closet (Structured Cabling System)?
Location of the cabling termination points. Connection of the horizontal cabling to the backbone wiring. AKA: Telecommunications Room (TR) AKA Telecommunications Enclosure (TE)
LLC
Logical Link Control
LTE
Long Term Evolution
LC
Lucent Connector - push/depress tab
Layer 2- Data Link Layer
MAC addresses, switches, frame, EUI
What is the purpose of MAC filtering on a wireless network?
MAC filtering can grant specific devices access to your network by adding their MAC address to the configuration.
Define MIMO as it applies to 802.11n.
MIMO = Multiple-input Multiple-output, uses separate antennas for each spatial stream.
What is the purpose of the power save mode in 802.11n?
MIMO power saving, Uses mutlple data paths only when faster data transmission is required.
multiple input multiple output (MIMO)
MIMO uses multiple antennas for transmission and reception. These antennas do not interfere with one another, thanks to MIMO's use of spatial multiplexing, which encodes data based on the antenna from which the data will be transmitted. Both reliability and throughput can be increased with MIMO's simultaneous use of multiple antennas.
100BASE-FX
MMF (multi-mode fiber) - 100Mbps, 2 km
100GBASE-SR10
MMF - 100Gbps, 125 m
10GBASE-SR
MMF - 10Gbps, 26m-400 m
10GBASE-SW
MMF - 10Gbps, 300 m
1000BASE-LX
MMF - 1Gbps, 5 km
MX
Mail Exchanger
MDF
Main Distribution Frame
MIB
Management Information Base
Define margin (dB) relative to cable measurements. What does it mean if the margin lists a negative value?
Margin for attenuation (insertion loss) is defined as the difference between the measured value and the limit for the test. If the margin shows a negative value, the test has failed.
MLA
Master License Agreement/Multilateral Agreement
MSA
Master Service Agreement
MSDS
Material Safety Data Sheet
What is the maximum speed and length for a Category 6 cabling?
Max speed = 1000 Mbps (1 gigabit) Max length = 100 meters
MTU
Maximum Transmission Unit
MTBF
Mean Time Between Failures
MTTR
Mean Time To Recovery
MT-RJ
Mechanical Transfer-Registered Jack
Expand the acronym MAC
Media Access Control
MAC
Media Access Control/Medium Access Control
MDI
Media Dependent Interface
MDIX
Media Dependent Interface Crossover
MGCP
Media Gateway Control Protocol
MTRJ
Media Termination Recommended Jack - 2 fiber strands in single connector - push/pull
Mbps
Megabits per second
MBps
Megabytes per second
MOA
Memorandum of Agreement
MOU
Memorandum of Understanding
MAN
Metropolitan Area Network
MAN (Expand and give definition/description)
Metropolitan Area Network - A network of users who share computer resources across a metropolitan area
MS-CHAP
Microsoft Challenge Handshake Authentication Protocol
MaaS
Mobility as a Service
Direct-sequence spread spectrum (DSSS)
Modulates data over an entire range of frequencies using a series symbols called chips. A chip is shorter in duration thana bit, meaning that chips are transmitted at a higher rate than the actual data. These chips not only represent encoded data to be transmitted, but also what appears to be random data. Because both parties involved in a DSSS communication know which chips represent actual data and which chips do not, if a third-party intercepted a DSSS transmission, it would be difficult for that party to eavesdrop on the data, because he would not easily know which chips represented valid bits. DSSS is more subject to environmental factors, as opposed to FHSS and OFDN because it uses of an entire frequency spectrum.
What is the purpose of Class D IP addresses?
Multicasting
MMF
Multimode Fiber
multimode fiber (MMF)
Multimode fiber-optic cabling has a core with a diameter large enough to permit the injection of light into the core at multiple angles. The different paths (that is, modes) that light travels can lead to multimode delay distortion, which causes bits to be received out of order because the pulses of light representing the bits traveled different paths (and therefore, different distances).
MIMO
Multiple Input, Multiple Output
MPLS
Multiprotocol Label Switching
MPLS
Multiprotocol Label Switching - WAN tech used by service providers (inserts 32-bit header between L2 and L3 headers)
MU-MIMO
Multiuser Multiple Input, Multiple Output
Signals travel in a cable at some percentage of the velocity of light. What is the term for this?
NVP = Nominal Velocity of Propagation
NFC
Near Field Communication
Define the term NEXT and what is measures.
Near-end Crosstalk = A measure of the level of crosstalk or signal coupling within a cable. A high NEXT (dB) value is desirable.
Internet Security Association and Key Management Protocol (ISAKMP)
Negotiates parameters for an IPsec session.
What is netsh
Netsh is a command-line scripting utility that allows you to display or modify the network configuration of a computer that is currently running. Netsh commands can be run by typing commands at the netsh prompt and they can be used in batch files or scripts. Remote computers and the local computer can be configured by using netsh commands.
NAC
Network Access Control
NAT
Network Address Translation
NAT
Network Address Translation - allows private IP addresses to translate into publicly-routable IP addresses
NAS
Network Attached Storage
NetBEUI
Network Basic Input/Output Extended User Interface
NetBIOS
Network Basic Input/Output System
What is a slowdown on network data traffic movement called?
Network Congestion
NCP
Network Control Protocol
NFS
Network File Service
Expand the acronym NIC
Network Interface Card
NIC
Network Interface Card
NIU
Network Interface Unit
NIDS
Network Intrusion Detection System
NIPS
Network Intrusion Prevention System
NNTP
Network News Transport Protocol
NTP
Network Time Protocol
NGFW
Next-Generation Firewall
Can private IP addresses be routed?
No, they are called "non-Internet routable IP addresses" and are blocked by ISPs.
NDR
Non-Delivery Receipt
How many private IP addresses be routed?
None
The network interface layer of the TCP/IP model defines how the host connects to which network?
Not dicttated by TCP/IP
What is a measure of fiber's light acceptance?
Numerical Aperture
What does OUI represent?
OUI identifies the manufacturer of the network hardware. It is the first 6 digits or 3 bytes of a MAC address.
A network interface card has the MAC address 00-00-86-15-7A. From this information specify the OUI. A. There is not sufficient information to specifcy the OUI B. The OUI is 86-15-7A. C. The OUI is 86-00-00 D. The OUI is 00-00-86
OUI, Organizatiionally Unique Identifier = D. The OUI is 00-00-86
demilitarized zone (DMZ)
Often contains servers that should be accessible from the Internet. This approach would, for example, allow users on the Internet to initiate an e-mail or a web session coming into an organization's e-mail or web server. However, other protocols would be blocked.
integrated services (IntServ)
Often referred to as hard QoS because IntServ can make strict bandwidth reservations. IntServ uses signaling among network devices to provide bandwidth reservations. Resource Reservation Protocol (RSVP) is an example of an IntServ approach to QoS. Because IntServ must be configured on every router along a packet's path, a primary drawback of IntServ is its lack of scalability.
administrator account
On a Windows system, the default account that has rights to access everything and to assign rights to other users on the network. Unlike other user accounts, the Administrator account cannot be deleted.
ping command
One of the most commonly used command-line commands. It can check IP connectivity between two network devices. Multiple platforms (for example, routers, switches, and hosts) support the ping command.
AH (Authentication Header)
One of the two separate protocols IPsec consists of (the other being ESP). AH provides the authentication and integrity checking for data packets.
current state modulation
One way to electrically or optically represent a binary 1 or 0 is to use current state modulation, which represents a binary 1 with the presence of voltage (on a copper cable) or the presence of light (on a fiber-optic cable). Similarly, the absence of light or voltage represents a binary 0.
state transition modulation
One way to electrically or optically represent a binary 1 or 0 is to use the transition between a voltage level (for example, going from a state of no voltage to a state of voltage, or vice versa, on a copper cable) or the transition of having light or no light on a fiber optic cable to represent a binary 1. Similarly, a binary 0 is represented by having no transition in a voltage level or light level from one time period to the next. This approach of representing binary digits is called state transition modulation.
OCSP
Online Certificate Status Protocol
How does a switch provide a link with minimal collisions?
Only the 2 computers that established the link communicate over the channel.
OSPF
Open Shortest Path First
OSPF
Open Shortest Path First - link-state route based on available bandwidth (cost)
OSI Model (expand and define)
Open Systems Interconnection - A seven layer model that describes network functions. Provides a framework for networking that ensures compatibility in the network hardware and software and to accelerate the development of new networking technologies
OS
Operating System
OCx
Optical Carrier
OTDR
Optical Time Domain Reflectometer
optical carrier (OC)
Optical networks often use OC levels to indicate bandwidth. As a base reference point, the speed of an OC-1 link is 51.84 Mbps. Other OC levels are multiples of an OC-1. For example, an OC-3 link has three times the bandwidth of an OC-1 link (that is, 3 * 51.84 Mbps = 155.52 Mbps).
What is the purpose of a GBIC?
Optical-Electrical signal conversion. Used for trasmitting and receiving higher-speed signals over fiber-optic lines.
OUI
Organizationally Unique Identifier
Expand the acronym OUI. Where is OUI used?
Organizationally Unique Identifier - OUI is part of a MAC address (the first 6 digits / 3 bytes)
OFDM
Orthogonal frequency-division multiplexing - slow modulation rate w/ simultaneous transmission of data over 52 data streams
How does NAT (Network Address Translation) help protect outsider access to computers in a home network?
Outsiders only see the IP address of the router assigned by the ISP. The private IPs used internally are not known.
pretty good privacy (PGP)
PGP is a widely deployed asymmetric encryption algorithm and is often used to encrypt e-mail traffic.
PAP
Password Authentication Protocol
virtual switch
Performs Layer 2 functions (for example, VLAN separation and filtering) between various server instances running on a single physical server.
Password Authentication Protocol (PAP)
Performs one-way authentication (that is, a client authenticates with a server). However, a significant drawback to PPP, other than its unidirectional authentication, is its clear-text transmission of credentials, which could permit an eavesdropper to learn authentication credentials.
Domain Name System (DNS) server
Performs the task of taking a domain name (for example, www.ciscopress.com) and resolving that name into a corresponding IP address (for example, 10.1.2.3).
PDoS
Permanent Denial of Service
PVC
Permanent Virtual Circuit
PAN
Personal Area Network
PC
Personal Computer
PCM
Phase-Change Memory
RJ-11
Phone - 6-pin connector
In regard to a CAT6 cable, what pin numbers in an RJ-45 connector are used to carry data in a Fast Ethernet network?
Pins 1-2 & 3-6
POTS
Plain Old Telephone Service
PaaS
Platform as a Service
Plenum
Plenum cabling is fire retardant and minimizes toxic fumes released by network cabling if that cable were to catch on fire. As a result, plenum cabling is often a requirement of local fire codes for cable in raised flooring or in other open-air return ducts.
What cable has a special coating that emits less toxic smoke when burned?
Plenum-rated cable
PTP
Point-to-Point
PPP
Point-to-Point Protocol
PPPoE
Point-to-Point Protocol over Ethernet
PPTP
Point-to-Point Tunneling Protocol
PTR
Pointer
PAT
Port Address Translation
Expand and define PAT.
Port Address Translation - A technique that involves tracking a port number with the client computer's private address when translating to a public address. The router stores the home network's IP address and port number in a NAT lookup table. THe port number differentiates the computer that is establishing the connection to the Internet because the router uses the same address for all computers.
PAT
Port Address Translation - assigns port to inside local address to route to port on global address
What are two types of labeling commonly used in networks?
Port Labeling & System Labeling
What are well-known ports?
Ports 1-1023 reserved by Internet Corporation for Assigned Names and Numbers (ICANN)
POP
Post Office Protocol
POP3
Post Office Protocol version 3
Explain how power is provided to a passive RFID tag.
Power is provided by rectifying the RF energy transmitted from the reader that strikes the RF tag antenna.
PoE
Power over Ethernet
PSK
Pre-Shared Key
PGP
Pretty Good Privacy
STP - Spanning Tree Protocol
Prevent loops in switch
Firewall
Primarily a network security appliance, a firewall can protect a trusted network (for example, a corporate LAN) from an untrusted network (for example, the Internet) by allowing the trusted network to send traffic into the untrusted network and receive the return traffic from the untrusted network, while blocking traffic for sessions that were initiated on the untrusted network.
PRI
Primary Rate Interface
PUA
Privileged User Agreement
PDU
Protocol Data Unit
PIM
Protocol Independent Multicast - routes multicast traffic between multicast-enabled routers
P
Provider - service provider internal router
PE
Provider Edge - MPLS service provider's router that connects to customer router
satellite (WAN technology)
Provides WAN access to sites where terrestrial WAN solutions are unavailable. Satellite WAN connections can suffer from long round-trip delay (which can be unacceptable for latency-sensitive applications) and are susceptible to poor weather conditions.
Secure Sockets Layer (SSL)
Provides cryptography and reliability for upper layers (Layers 5[nd]7) of the OSI model. SSL, which was introduced in 1995, has largely been replaced by Transport Layer Security (TLS). However, recent versions of SSL (for example, SSL 3.3) have been enhanced to be more comparable with TLS. Both SSL and TLS are able to provide secure web browsing via HTTPS.
PKI
Public Key Infrastructure
PSTN
Public Switched Telephone Network
How many output power classes does Bluetooth have? List the power level and the operating range for each class.
Pwr Class Max Output Pwr Op Dist 1 20 dBm ~ 100 m 2 4 dBm ~ 10 m 3 0 dBm ~ 1 m
QSFP
Quad Small Form-Factor Pluggable
QoS
Quality of Service
omnidirectional antenna
Radiates power at relatively equal power levels in all directions (somewhat similar to the theoretical isotropic antenna). Omnidirectional antennas are popular in residential WLANs and SOHO locations.
RF
Radio Frequency
RFI
Radio Frequency Interference
RG
Radio Guide
RSTP
Rapid Spanning Tree Protocol
RTP
Real-Time Protocol
RTSP
Real-Time Streaming Protocol
What does "RX" signify?
Receive
RPO
Recovery Point Objective
RTO
Recovery Time Objective
RJ
Registered Jack
RAS
Remote Access Service
RADIUS
Remote Authentication Dial-In User Service
RDP
Remote Desktop Protocol
RSH
Remote Shell
RFP
Request for Proposal
two-factor authentication (TFA)
Requires two types of authentication from a user seeking admission to a network. For example, a user might need to know something (for example, a password) and have Something (for example, a specific fingerprint that can be checked with a biometric authentication device).
edge label switch router (ELSR)
Resides at the edge of an MPLS service provider's cloud and interconnects a service provider to one or more customers.
label switch router (LSR
Resides inside a service provider's MPLS cloud and makes frame forwarding decisions based on labels applied to frames.
RARP
Reverse Address Resolution Protocol
What are the most common architectures for LANs?
Ring, Bus, Star
RSA
Rivest, Shamir, Adelman
RTT
Round Trip Time or Real Transfer Time
RIP
Routing Information Protocol - route based on hop count
RIP
Routing Internet Protocol
Layer 3 - Network Layer
Routing, IP, fragments frames, packets
access control list (ACL)
Rules typically applied to router interfaces, which specify permitted and denied traffic.
1000BASE-SX
SMF (Single-mode fiber) - 1Gbps, 5 km
100GBASE-LR4
SMF - 100Gbps, 10 km
100GBASE-ER4
SMF - 100Gbps, 40 km
10GBASE-LW
SMF - 10Gbps, 10 km
10GBASE-LR
SMF - 10Gbps, 10-25 km
10GBASE-ER
SMF - 10Gbps, 40 km
10GBASE-EW
SMF - 10Gbps, 40 km
1000BASE-LH
SMF - 1Gbps, 10 km
1000BASE-ZX
SMF - 1Gbps, 70 km
single-mode fiber (SMF)
SMF cabling has a core with a diameter large enough to permit only a single path for light pulses (that is, only one mode of propagation). By having a single path for light to travel, SMF eliminates the concern of multimode delay distortion.
What is the purpose of the SSID, and what can a network administrator do to protect a network from hackers who might have learned the SSID?
SSID is a name used to identify your wireless network and is used by your access point or wireless router to establish an association. As an administrator you can change the SSID often to avoid letting hackers access your home network.
SCP
Secure Copy Protocol
SFTP
Secure File Transfer Protocol
SHA
Secure Hash Algorithm
SSH
Secure Shell
SSL
Secure Sockets Layer
SA
Security Association
SIEM
Security Information and Event Management
remote-access VPN
See client-to-site VPN.
slash notation
See prefix notation.
fox and hound
See toner probe.
CSMA/CD - Carrier Sense Multiple Access / Collision Detect
Senses data across multiple devices on network to detect when two stations talk at once - Half-duplex Ethernet
link-state advertisement (LSA)
Sent by routers in a network to advertise the networks the routers know how to reach. Routers use those LSAs to construct a topological map of a network. The algorithm run against this topological map is Dijkstra's shortest path first algorithm.
DB-9 (RS-232)
Serial - 9-ping connector
SLIP
Serial Line Internet Protocol
SMB
Server Message Block
SLA
Service Level Agreement
SSID
Service Set Identifier
SDP
Session Description Protocol
SIP
Session Initiation Protocol
Expand STP.
Shielded Twisted Pair
SMS
Short Message Service
classless interdomain routing (CIDR)
Shortens a classful subnet mask by removing right-justified 1s from a classful mask. As a result, CIDR allows contiguous classful networks to be aggregated. This process is sometimes called route aggregation.
SPB
Shortest Path Bridging
Layer 1 - Physical
Signaling, cabling, connectors - bad cables, punch-downs, loopback, adapter cards
packet-switched connection
Similar to a dedicated leased line, because most packet-switched networks are always on. However, unlike a dedicated leased line, packet-switched connections allow multiple customers to share a service provider's bandwidth.
multifactor authentication
Similar to two-factor authentication, multifactor authentication requires two or more types of successful authentication before granting access to a network.
SGCP
Simple Gateway Control Protocol
SMTP
Simple Mail Transfer Protocol
SNMP
Simple Network Management Protocol
SNTP
Simple Network Time Protocol
SMF
Single-Mode Fiber
SFP
Small Form-factor Pluggable
SOHO
Small Office Home Office
SDN
Software Defined Network
SDLC
Software Development Life Cycle
SaaS
Software as a Service
virtual private network (VPN)
Some VPNs can support secure communication between two sites over an untrusted network (for example, the Internet).
toner probe
Sometimes called a fox and hound, a toner probe allows you to place a tone generator at one end of the connection (for example, in someone's office), and use a probe on the punch-down block to audibly detect to which pair of wires the tone generator is connected.
STP
Spanning Tree Protocol/Shielded Twisted Pair
private IP addresses
Specific Class A, B, and C networks have been designed for private use. Although these networks are routable (with the exception of the 169.254.0.0-169.254.255.255 address range), within the organization, service providers do not route these private networks over the public Internet.
SC
Standard Connector/Subscriber Connector
SOP
Standard Operating Procedure
SPS
Standby Power Supply
What is 8P8C, and what connector type is most associated with it?
Stands for 8-pin 8-conductors and is defined by ANSI/TIA-968-A and B but is commonly called RJ-45 by both professionals and end users.
SOA
Start of Authority
SPI
Stateful Packet Inspection
SLAAC
Stateless Address Auto Configuration
SOW
Statement of Work
SNAT
Static Network Address Translation/Source Network Address Translation
Explain the difference between store-and-forward and the cut-through modes on a switch.
Store-and-foward recieves an entire frame of data before considering forwarding of that packet. The switch checks for errors before sending but this increases switch latency. Cut-through mode forwards the packet as soon as the MAC address has been read. There is no error detection but this minimizes switch latency.
ST
Straight Tip or Snap Twist
ST connector
Straight tip - Used w/ MMF (push in connector and twist)
Define "Pulse dispersion".
Stretching of received pulse width because of multiple paths taken by the light
What is the purpose of a subnet mask?
Subnetting is used to partition networks into subnets. A subnet mask identifies which bits in an IP address are to be used to represent the network/subnet portion of an IP address.
SC
Subscriber/Standard/Square Connector - push/pull
SCADA
Supervisory Control and Data Acquisition
time-division multiplexing (TDM)
Supports different communication sessions (for example, different telephone conversations in a telephony network) on the same physical medium, by allowing sessions to take turns. For a brief period of time, defined as a time slot, data from the first session is sent, followed by data from the second sessions. This continues until all sessions have had a turn, and the process repeats itself.
SVC
Switched Virtual Circuit
Explain how a switch learns MAC addresses and where a switch stores the addresses.
Switches learn MAC addresses of the connected networks by extracting MAC address information from the headers of transmitted data packets. This information is stored in the CAM - Content Addressable Memory.
SDSL
Symmetrical Digital Subscriber Line
SONET
Synchronous Optical Network
SYSLOG
System Log
T1
T1 circuits were originally used in telephony networks, with the intent of one voice conversation being carried in a single channel (that is, a single DS0). A T1 circuit consists of 24 DS0s, and the bandwidth of a T1 circuit is 1.544 Mbps.
Why is balance an issue in UTP cables, and what is TCL?
TCL = Transverse conversion loss - The balance or symmetry over the wire pairs helps minimize the unwanted leakage of the signal
Layer 4 - Transport Layer
TCP/UPD
568A/568B standards
Telecommunications standards from the Telecommunications Industry Association (TIA) and the Electronics Industry Association (EIA). These 568 standards specify the pin arrangements for the RJ-45 connectors on UTP or STP cables. The number 568 refers to the order in which the wires within the UTP cable are terminated and attached to the connector.
Telco
Telecommunications Company
TKIP
Temporal Key Integrity Protocol
TACACS
Terminal Access Control Access Control System
TACACS+
Terminal Access Control Access Control System+
TA
Terminal Adaptor
T1
Terrestrial Carrier Level 1
ARP ping
The ARP utility that resolves IP addresses to MAC addresses. The ARP ping utility tests connectivity by pinging a MAC address directly.
committed information rate (CIR)
The CIR of an interface is the average traffic rate over the period of a second.
AAAA record
The DNS record that maps a hostname to a 128-bit IPv6 address. This is also known as the IPv6 address record.
100BaseT
The IEEE 802.3 specification for running Ethernet at 100 Mbps over twisted-pair cabling. The maximum length of a 100BASET segment is 100 meters (328 feet).
What is the logical address?
The IP address location of a network and the address location of a host in a a network.
default gateway
The IP address of a router (or multilayer switch) to which a networked device sends traffic destined for a subnet other than the device's local subnet.
What is the purpose of the Internet layer in the TCP/IP protocol suite?
The Internet Layer defines the protocols used for addressing and routing data packets. Protocols included: IP, ARP, ICMP, IGMP.
network interface layer
The Network Interface Layer of the TCP/IP stack (also known as the network access layer) encompasses the technologies addressed by Layers 1 and 2 (that is, the physical and data link layers) of the OSI model.
Time To Live (TTL)
The TTL field in an IP header is decremented once for each router hop. Therefore, if the value in a TTL field is reduced to 0, a router discards the frame and sends a time exceeded ICMP message back to the source.
Wi-Fi Protected Access (WPA)
The Wi-Fi Alliance (a nonprofit organization formed to certify interoperability of wireless devices) developed its own security standard to address the weaknesses of Wired Equivalent Privacy (WEP). This new security standard was called Wi-Fi Protected Access (WPA) Version 1.
ACK
The acknowledgment message sent between two hosts during a TCP session
Define "mode field diameter".
The actual guided optical power distribution, which is typically a micron or so larger than the core diameter; single-mode fiber specifications typically list the mode field diameter.
logical topology
The actual traffic flow of a network determines the network's logical topology.
Define the term Protocol Topology
The architecture of a network
What is an association on a bridge, and how is it used?
The bridge monitors the data on its ports to check for an association between the destination MAC address of the Ethernet frames to any of the hosts connected to its ports. An association indicates that the destination MAC address for a host is connected to one of the ports on the bridge. If an association is found, the data is forwarded to that port.
What is Intermediate Cross-connect (IC) (Structured Cabling System)?
The building's conection point to the campus backbone, which links the Main Cross-connect (MC) to the Horizontal Cross-connect (HC). AKA - Building Distributor (BD)
What is Full-duplex?
The capability to transmit and receive at the same time.
What is Horizontal Cross-connect (Structured Cabling System)?
The connection between the building distributors and the horizontal cabling to the work area or workstation outlet. AKA - Floor Distributors (FDs)
What part of an optical fiber carries the light?
The core
What does it mean for a wireless networking device to be Wi-Fi compliant?
The device is certified by the Wi-Fi Alliance and 801.11x standards
Why are narrower spectra advantageous in optical systems?
The dispersion effects of the fiber on pulse width are reduced, and thus puse degradation over long distances is minimized
What does an empty ARP cache indicate?
The entries have expired. The ARP cache is temporary storage.
What is an error threshold, and which switch mode is it associated with?
The error threshold is the point at which the number of errors in the data packets has reached a threshold, and the switch changes from cut-through mode to store-and-foward mode. The switch mode associated is "adaptive cut-through" (a combination of cut-through and store-and-forward modes)
Why are power sum measurements critical for high-speed commmunication of UTP?
The gigabit data rate capability of twisted-pair requires the use of all four wire pairs in the calbe, with each pair handling 250Mbps of data. (4x250Mbps = 1Gbps) Hence the need to obtain the combine performance measurements of all four wire pairs. ( Power sum measurements provide a measure of the total crosstalk of all cable pairs, ensuring that the cable can simultaneously carry data traffic on all four wire pairs with minimal interference. )
maximum transmission unit (MTU)
The largest packet size supported on an interface.
Define "aging time" on a switch.
The length of time a MAC address remains assigned to a port.
What is the limit on the bend radius for a UTP cable, and why is this important?
The limit on the bend radius is four times the outer jacket diameter. The reason for this is bends exceeding the limit can introduce attenuation loss.
What is Work Area (Structured Cabling System)?
The location of the computers, printers, patch cables, jacks, computer adapter cables, and fiber jumpers.
attenuation
The loss of signal experienced as data transmits over distance and across the network medium.
Availability
The measure of a network's uptime.
Latency
The measure of delay in a network.
Reliability
The measure of how error-free a network transmits packets.
Define propagation delay.
The measure of the amount of time it takes for a signal to propagate from one end of the cable to the other. The EIA/TIA specification allows for 548 ns for the max 100-meter run for CAT5e, CAT6, CAT6a, CAT7, and CAT7a.
Star Topology
The most common networking topology in today's LANs, where all networking devices connect to a central switch or hub
protocol data unit (PDU)
The name given to data at different layers of the OSI model. Specifically, the PDU for Layer 4 is segment. The Layer 3 PDU is packet, the Layer 2 PDU is frame, and the Layer 1 PDU is bit.
Define enterprise network.
The network used by a large company.
block size
The number of IP addresses in a subnet, including the subnet's address and the subnet's directed broadcast address.
What happens if a MAC address is not stored in CAM on a switch?
The packet is transmitted out all switch ports except for the port where the packet was received. This is called flooding
Ports
The physical input / output interfaces to networking hardware
What is a UTP link test?
The point from one cable termination to another = Link
What is meant by the zero-dispersion wavelength?
The point were dispersion is actually zero as determined by the refractive index profile. Near 1310nm
What is the building entrance (Structured Cabling System)?
The point where the external cabling and wireless services interconnect with the internal building cabling in the equipment room (ER). AKA Entrance Facilities (EF). Pubic and private network cables enter the building at this point
authentication
The process by which a user's identity is validated on a network. The most common authentication method is a username and password combination.
binding
The process of associating a protocol with a NIC.
Define "refractive index".
The ratio of speed of light in free space to its speed in a given material.
tip and ring
The red and green wires found in an RJ-11 wall jacks, which carry voice, ringing voltage, and signaling information between an analog device (for example, a phone or a modem) and an RJ-11 wall jack.
Define the term backscatter.
The reflection of radio waves striking an RFID tag and reflecting back to the transmitter source.
ARIN (American Registry for Internet Numbers)
The regional Internet registry responsible for managing both IPv4 and IPv6 IP number distribution.
What is a Color Map? (Cable Termination)
The specification of which wire color connects to each pin on a connector.
baud rate
The speed or rate of signal transfer. Baud rate bandwidth is measured in cycles per second, or hertz (Hz). The word baud is derived from the name of French telegraphy expert J. M. Baudot.
BCP (business continuity plan)
The strategy for addressing potential threats to a company and creation of systems to aid in the prevention of threats and recovery from problems.
Offsite
The term offsite in the context of virtualization technologies refers to hosting virtual devices on hardware physically located in a service provider's data center.
Onsite
The term onsite in the context of virtualization technologies refers to hosting virtual devices on hardware physically located in a corporate data center.
Define power sum measurements.
The total crosstalk of all cable pairs. This test ensures that the cable can carry data traffic on all four pairs at the same time with minimal interference.
What does cross-connection mean?
The transmit and receive pairs on the twist-pair cable are crossed to properly align each for data communication.
transport layer (TCP/IP stack)
The transport layer of the TCP/IP stack maps to Layer 4 (transport layer) of the OSI model. The two primary protocols found at the TCP/IP stack's transport layer are TCP and UDP.
Jitter
The uneven arrival of packets.
What must the FHSS trasmitting and receiving units know in order to communicate?
The units must know the hopping sequence.
physical topology
The way a network's components are physically interconnected determines the network's physical topology.
bandwidth
The width of the range of electrical frequencies, or how many channels the medium can support. Bandwidth correlates to the amount of data that can traverse the medium at one time, but other factors determine the maximum speed supported by a cable.
What is Work Area Outlet (Structured Cabling System)?
The workstation used to connect devices - PCs, printers, servers, phones, televisions, WAPs to the cable plant typically with CATX cabling and coaxial cables AKA - Telecommunications Outlet (TO)
public switched telephone network (PSTN)
The worldwide telephony network consisting of multiple telephone carriers.
distributed denial of service (DDoS)
These attacks can increase the amount of traffic flooded to a target system. Specifically an attacker compromises multiple systems, and those compromised systems, called zombies, can be instructed by the attacker to simultaneously launch a DDoS attack against a target system.
buffer overflow
This attack occurs when an attacker leverages a vulnerability in an application, causing data to be written to a memory area (that is, a buffer) that's being used by a different application.
full duplex
This connection allows a device to simultaneously transmit and receive data.
customer premise equipment (CPE)
This device resides at a customer site. A router, as an example, can be a CPE that connects a customer with an MPLS service provider.
poison reverse
This feature of a distance-vector routing protocol causes a route received on one interface to be advertised back out of that same interface with a metric considered to be infinite.
split horizon
This feature of a distance-vector routing protocol prevents a route learned on one interface from being advertised back out of that same interface.
Internet layer
This layer of the TCP/IP stack maps to Layer 3 (network layer) of the OSI model. Although multiple routed protocols (for example, IPv4 and IPv6) may reside at the OSI model's network layer, the Internet layer of the TCP/IP stack focuses on IP as the protocol to be routed through a network.
TDM
Time Division Multiplexing
TDR
Time Domain Reflectometer
Expand the acronym TTL.
Time To Live
TTL
Time to Live
What is the purpose of an ARP request?
To ask which network interface has this IP address.
What is the purpose of a private IP address?
To be used in intranets / internal networks.
What is the purpose of an access point?
To connect to a wired connection
What is the purpose of the inquiry procedure in Bluetooth?
To determine if any other Bluetooth devices are available and to allow itself to be discovered.
What is the purpose of the paging procedure in Bluetooth?
To establish and synchronize a connection between two Bluetooth devices.
What is the purpose of an extended service set?
To extend user mobility / A network with multiple access points
What is the purpose of a range expander?
To extend wi-fi coverage. The device relays the wireless signals from an access point or wireless router into areas with a weak signal or not signal at all
What is the purpose of a sequence number (SEQ) in TCP data packets?
To keep track of the packets being transferred.
link efficiency
To make the most of the limited bandwidth available on slower speed links, you might choose to implement compression or link fragmentation and interleaving (LFI). These QoS mechanisms are examples of link efficiency mechanisms.
What is the purpose of a lacing tool?
To match the wire colors to the proper order (T568A/T568B) displayed on the sides of the lacing tool.
electrostatic discharge (ESD) wrist strap
To prevent static electricity in your body from damaging electrical components on a circuit board, you can wear an ESD wrist strap. The strap is equipped with a clip that you can attach to something with a ground potential (for example, a large metal desk). While wearing the wrist strap, if you have any static buildup in your body, the static flows to the object with a ground potential to which your strap is clipped, thus avoiding damage to any electrical components that you might touch.
What is the purpose of an ARP reply?
To return the hardware address of the destination host determined by the ARP request.
A router uses the network address on a data packet for what purpose?
To route packets to their destination address.
Why is checking the lights of a networking device that connects to the ISP important?
To verify your connect is up. Incorrect lights can indicate a connection problem with you cable modem, DLS modem, or telephone connection.
twisted-pair cable
Today's most popular media type is twisted-pair cable, where individually insulated copper strands are intertwined into a twisted-pair cable. Two categories of twisted-pair cable include shielded twisted pair (STP) and unshielded twisted pair (UTP).
What device is used for troubleshooting cable termination?
Toner Probe
TCP
Transmission Control Protocol
Expand the acronym TCP/IP
Transmission Control Protocol / Internet Protocol
TCP/IP
Transmission Control Protocol/Internet Protocol
Broadcast
Transmission of data by a hub to all devices connected ot its ports
What does "TX" signify?
Transmit
Define the term cross-connect input.
Transmit and receive pairs are internally swapped to maintain proper signal alignment of the TX and RX pairs.
TLS
Transport Layer Security
TMS
Transportation Management System
TFTP
Trivial File Transfer Protocol
True or false: A hub is also called a multiport repeater.
True
True or False: One room can serve as the entrance facility, the equipment room, and the telecommunications closet.
True.
True or false: Delay skew is critical because if the wire lengths of different wire pairs are significantly different, the data will arrive at the receiver at different times, potentially creating distortion of the data.
True.
True or false: In regard to CAT5e/CAT6 cable operating in half-duplex mode for Ethernet or Fast Ethernet, pins 1-2 and 3-6 are used to carry the data.
True.
TPM
Trusted Platform Module
TTLS
Tunneled Transport Layer Security
TOS
Type of Service
bus topology
Typically, it uses a cable running through the area requiring connectivity, and devices to be networked can tap into that cable.
In Windows 10, how can you find the Ethernet (MAC) address?
Typing "ipconfig /all" in a command prompt (cmd) will display the MAC address aka the physical address
Expand UDP and explain what it is.
UDP = User Datagram Protocol is a connectionless protocol meaning that packets are transferred over the network without a connection being established and without any acknowledgement that the data packets arrvied at the destination.
traceroute command
UNIX command that display every router hop along the path from a source host to a destination host on an IP network. Information about the router hop can include the IP address of the router hop and the round-trip delay of that router hop.
Which cable, UTP or STP, is preferred by the industry?
UTP
UPC
Ultra Polished Connector
unidirectional antenna
Unidirectional antennas can focus their power in a specific direction, thus avoiding potential interference with other wireless devices and perhaps reaching greater distances than those possible with omnidirectional antennas. One application for unidirectional antennas is interconnecting two nearby buildings.
UC
Unified Communications
UTM
Unified Threat Management
URL
Uniform Resource Locator
UPS
Uninterruptible Power Supply
UNC
Universal Naming Convention
USB
Universal Serial Bus
Expand UTP.
Unshielded Twisted Pair
UTP
Unshielded Twisted Pair
Border Gateway Protocol (BGP)
Used between gateway hosts on the Internet. BGP examines the routing table, which contains a list of known routers, the addresses they can reach, and a cost metric associated with the path to each router so that the best available route is chosen. BGP communicates between the routers using TCP.
Active Directory
Used in Windows network environments, this is a directory services system that enables network objects to be stored in a database. This database can then be divided and distributed among different servers on the network.
carrier sense multiple access collision detect (CSMA/CD)
Used on an Ethernet network to help prevent a collision from occurring and to recover if a collision does occur. CSMA/CD is only needed on half-duplex connections.
Crimper
Used to attach a connector (for example, an RJ-45 connector) to the end of an unshielded twisted-pair (UTP) cable.
What is a patch cable?
Used to make the physical connection from the computer to the wall plate.
What is the purpose of an optical attenuator?
Used to reduce the received signal level (RSL)
UDP
User Datagram Protocol
What are three advantages of a wireless network?
User mobility, simple installations, no cables
Wi-Fi Protected Access Version 2 (WPA2)
Uses Counter Mode with Cipher Block Chaining Message Authentication Code Protocol (CCMP) for integrity checking and Advanced Encryption Standard (AES) for encryption. These algorithms enhance the security offered by WPA.
virtual PBX
Usually a VoIP telephony solution hosted by a service provider, which interconnects with a company's existing telephone system.
VTP
VLAN Trunk Protocol
VDSL
Variable Digital Subscriber Line
VTC
Video Teleconference
VLAN
Virtual Local Area Network
VNC
Virtual Network Connection
VPN
Virtual Private Network
VRRP
Virtual Router Redundancy Protocol
VRF
Virtual Routing Forwarding
VoIP
Voice over IP
Packet-switched connection
WAN connection allowing multile customers to share an SP's bandwidth (Frame Relay)
Circuit-switched connections
WAN connection brought up on an as-needed basis (ISDN - Integrated Services Digital Network)
Dedicated Leased Line
WAN connection interconnecting two sites (T1, T3 circuits)
extended service set (ESS)
WLANs containing more than one AP are called ESS WLANs. Like BSS WLANs, ESS WLANs operate in infrastructure mode. When you have more than one AP, take care to prevent one AP from interfering with another. Specifically, nonoverlapping channels (that is, channels 1, 6, and 11 for the 2.4-GHz band) should be selected for adjacent wireless coverage areas.
basic service set (BSS)
WLANs that have just one AP are called BSS WLANs. BSS WLANs are said to run in infrastructure mode because wireless clients connect to an AP, which is typically connected to a wired network infrastructure. A BSS network is often used in residential and SOHO locations, where the signal strength provided by a single AP is sufficient to service all of the WLAN's wireless clients.
What is the WO and what is its purpose?
WO = Work Area Outlet, The workstation used to connected devices ot the cable plant.
WMS
Warehouse Management System
WAF
Web Application Firewall
congestion management
When a device, such as a switch or router, receives traffic faster than it can be transmitted, the device attempts to buffer (or store) the extra traffic until bandwidth becomes available. This buffering process is called queuing or congestion management.
hub-and-spoke topology
When interconnecting multiple sites (for example, multiple corporate locations) via WAN links, a hub-and-spoke topology has a WAN link from each remote site (a spoke site) to the main site (the hub site).
punch-down tool
When terminating wires on a punch-down block (for example, a 110 block), you should use a punch-down tool, which is designed to properly insert an insulated wire between two contact blades in a punch down block, without damaging the blades.
bit-error rate tester (BERT)
When troubleshooting a link where you suspect a high bit-error rate (BER), you can use a piece of test equipment called a bit-error rate tester (BERT), which contains both a pattern generator (which can generate a variety of bit patterns) and an error detector (which is synchronized with the pattern generator and can determine the number of bit errors) and can calculate a BER for the tested transmission link.
What is Termination (Structured Cabling System)?
Where the cable connects to a jack in a wall plate, a patch panel, or an RJ-45 modular plug.
orthogonal frequency-division multiplexing (OFDM)
Whereas DSSS uses a high modulation rate for the symbols it sends, OFDM uses a relatively slow modulation rate for symbols. This slower modulation rate, combined with the simultaneous transmission of data over 52 data streams, helps OFDM support high data rates while resisting crosstalk between the various data streams.
You have the choice of selecting a networking device with WEP or a device with WPA. Which offers better security and why?
Wi-Fi Protected Access (WPA) offers better security because it uses a strong encryption method than WEP.
WPA
WiFi Protected Access
WPS
WiFi Protected Setup
Expand the acronym WAN
Wide Area Network
WAN
Wide Area Network
WAN (Expand and give definition/description)
Wide Area Network - A network of users who share computer resources over a large scale geographical area
WEP
Wired Equivalent Privacy
CSMA/CA - CSMA / Collision Avoidance
Wireless (Ready To Send - Clear To Send)
WAP
Wireless Application Protocol/Wireless Access Point
WLAN
Wireless Local Area Network
Asymmetric encryption
With asymmetric encryption, the sender and receiver of a packet use different keys.
channel bonding
With channel bonding, two wireless bands can be logically bonded together, forming a band with twice the bandwidth of an individual band. Some literature refers to channel bonding as 40-MHz mode, which refers to the bonding of two adjacent 20-MHz bands into a 40-MHz band.
symmetric encryption
With symmetric encryption, both the sender and receiver of a packet use the same key (a shared key) for encryption and decryption.
WWN
World Wide Name
Is a high PSNEXT measurement desirable?
Yes, becuase it indicates better cable performance
Zeroconf
Zero Configuration
define network segment
a bus and all devices connected to the bus. it is a single collision domain.
define wlan
a lan made up of wireless networking devices
Name each network topology shown
a. Mesh b. Bus c. Ring d. Star
Which of the following is not a step in building an office LAN? a. Obtaining proper government permits b. Configuring the network settings c. Connecting the devices together d. Network documentation
a. Obtaining proper government permits
define hub
an older technology that interconnects network components. Layer 1 device that repeats traffic out all ports
The term deterministic means a. access to the network is provided at random time intervals b. access to the network is provided using CSMA/CD c. access to the network is provided at fixed time intervals d. none of these answers are correct
c. access to the network is provided at fixed time intervals
unshielded twisted-pair (UTP)
cable Blocks EMI from the copper strands making up a twisted-pair cable by twisting the strands more tightly (that is, more twists per centimeter [cm]). By wrapping these strands around each other, the wires insulate each other from EMI.
shielded twisted-pair (STP)
cable STP cabling prevents wires in a cable from acting as an antenna, which might receive or transmit EMI. STP cable might have a metallic shielding, similar to the braided wire that acts as an outer conductor in a coaxial cable.
What are the most common types of equipment that are used to establish broadband connections to ISPs?
cable modem and DSL
What are the basic network components
client, server, hub, switch, router, media, and WAN link
define full-mesh topology
directly connect every wan site to every other site. traffic path always takes the optimal path and network is highly fault tolerant.
The IPv4 address 192.168.12.2 is an example of which address format?
dotted decimal
XML
eXtensible Markup Language
define FDDI
fiber distributed data interface: a variant of a ring topology that contains two fiber optics cables as the rings. The rings sends data in opposite directions (counter-rotating rings) which created redundancy.
define san
high-speed highly reliable network for the express purpose of transmitting stored data
what is a partial-mesh topology
hybrid of mesh and hub-and-spoke topologies. designed to offer an optimal route between selected sites and avoiding expense of interconnecting every site. Try to add links interconnecting sites that have higher volumes of traffic
define wan
interconnects network components that are geographically separated (examples of WAN technologies multiprotocol label switching (MPLS) and asynchronous transfer mode (ATM))
Define lan
interconnects network components within a local area
define switch
interconnects network components. A layer 2 device that makes forwarding decisions based on MAC.
define hub-and-spoke topology
it has a wan link from each remote site (spoke) to the main site (hub). With wan links, a service provider is paid a recurring fee for each link which results in decrease cost by not directly connecting any two spoke locations
Define server
it serves up resources to a network to include email, web pages, or files
define bus topology
it typically uses a cable running through the are needing connectivity. devices that need to connect tap into the cable, using T connectors or vampire taps. Also contains terminators at each end
What are the different type networks categories
lan, wan, wlan, storage area network (SAN), campus area network (can), metropolitan area network (man) personal area network (pan)
define router
layer 3 device the makes forwarding decision based on logical network addresses using IP addressing
Layer 7 - Application Layer
layer we see, HTTP, FTP, DNS, POP3
Should the expected + loss of a 20-meter UTP cable be greater than or less than that of a 90-meter UTP cable?
less than
What is the advantage of fusion splicing over mechanical splicing?
low insertion losses
define man
more widespread than a can but less than a wan. its interconnected scattered throughout a metropolitan area
Supervisory Control and Data Acquisition (SCADA)
network Specialized network that provides control of remote equipment for monitoring and control of that equipment. A power plant or gas refinery would have a SCADA network.
How many network and host bits are in a Class C network address?
network bits = 24, host bits = 8
define pan
network whose scale is smaller than a lan (ie pc to digital camera via USB or bluetooth connection between cellphone and car audio system). Range of the network connection is limited to just a few meters.
What command would you use to ping 10.3.9.42 indefinitely?
ping 10.3.9.42 -t
What command would you use to ping 128.168.5.36 20 times with 1024 bytes of data?
ping 128.168.5.36 -n 20 -l 1024
define can
several lan interconnected across an universities
POP3 - Post Office Protocol version 3
tcp/110 - basic mail transfer
NNTP - Network New Transport Protocol
tcp/119 - posting and reading articles on Usenet news servers
NetBIOS - Network Basic Input/Output System
tcp/139, udp/137, udp/138 - Network communication servers for LANs that use NetBIOS
IMAP - Internet Message Access Protocol v4
tcp/143 - Includes management of email inbox from multiple clients
SNMP Trap
tcp/162, udp/162 - notification sent from SNMP agent to SNMP manager
H.323 - H.32x protocol
tcp/1720 - VoIP setup and management
FTP - File Transfer Protocol
tcp/20 (active mode data), tcp/21 (control) - transfer files between systems with authentication
SSH - Secure Shell
tcp/22 - Encrypted communication link
SFTP - Secure FTP
tcp/22 - SSH File Transfer Protocol
Telnet
tcp/23 - Unencrypted remote communication
SMTP - Simple Mail Transfer Protocol
tcp/25 - serv-to-serv email transfer / send email
RDP - Remote Desktop Protocol
tcp/3389 - share desktop remotely
LDAP - Lightweight Directory Access Protocol
tcp/389 - Store and retrieve info in a network directory
HTTPS - HTTP Secure
tcp/443 - secure communication in browser
SMB - Server Message Block
tcp/445 - file sharing/printer sharing Windows
RTP - Real-time Transport Protocol
tcp/5004,5005 udp/5004,5005 - Deliver media-based data
SIP - Session Initiation Protocol
tcp/5060, tcp/5061 - Setup and manage VoIP sessions
rsh - Remote Shell
tcp/514 - execute commands on computer from remote user
RTSP - Real-time Streaming Protocol
tcp/554, udp/554 - communicates w/ media server and controls playback of media files
LDAPS - LDAP Secure
tcp/636 - non-standard LDAP over SSL
HTTP - Hypertext Transfer Protocol
tcp/80 - communication in browser and other applications
define physical topology
that way a networks components are physically interconnected
define logical topology
the actual traffic flow of a network to determine the topology
Define client
the device an end user uses to access a network (ie workstation, laptop, smartphone etc...)
define media
the means in which devices are connected (ie copper cabling, fiber-optic, radio waves)
define star topology
there is a hub, switch, or router in the center and a collection of clients individually connected to the center device.
define ring topology
traffic flows in a circular fashion around a closed network loop. It sends data in a single direction to each connected device in turn until the intended destination receives the data.
What are the typical core/cladding sizes (in microns) for multimode fiber?
typical = 50 and 62.5 , cladding = 125
NTP - Network Time Protocol
udp/123 - Sync clocks between devices
SNMP - SImple Network Management Protocol
udp/161 - gather data from network devices
MGCP - Media Gateway Control Protocol
udp/2427, udp/2727 - Call control for VoIP
DNS - Domain Name System
udp/53 - Converts names to IP addresses
DHCP - Dynamic Host Configuration Protocol
udp/67, udp/68 - Automated config of IP address, subnet mask and other options
TFTP - Trivial FTP
udp/69 - file transfer w/o authentication or encryption