Chapter 11
The TCP/IP model consists of which four layers?
(1) Application, (2) Transport, (3) Internet, and (4) Link Was developed before the OSI reference model was created.
__________ technology (LAN) can support only a single communication channel, whereas _______ technology can support multiple simultaneous signals
(1) Baseband, (2) Broadband Ethernet is an example of Baseband. Cable modems are example of broadband.
What are the three steps of the TCP handshake process?
(1) Client sends SYN flagged packet to server (2) Server responds with SYN/ACK flagged packet back to client (3) Client sends ACK flagged packet back to the server
_________ refers to two-way communication, but only one direction can send data at a time, while ______ is also two-way communication but can be sent in both directions simultaneously
(1) Half-Duplex, and (2) Full-Duplex
EIA/TIA-232, EIA/TIA-449, X.21, HSSI, SONET, V.24, and V.35 are protocols of which OSI layer?
(1) Physical
What are the 7 layers of the OSI model?
(1) Physical, (2) Data link, (3) Network (4) Transport, (5) Session (6) Presentation (7) Application. Please do not throw sausage pizza away. These are all logical communication types (computer to computer).
Network interface cards (NICs), hubs, repeaters, concentrators, and amplifiers operate at which layer?
(1) Physical. These are physical networking hardware devices.
Headers are added at the ______ layer, while footers are added at the _______ layer
(1) Presentation, (2) Data Link
_______ is the IEEE standard for wireless network communications
802.11 There are versions a, b, g, n, and ac.. n has the most mbps (600) . The 802.11 standard also defines Wired Equivalent Privacy (WEP)
The two primary Transport layer protocols of TCP/IP are _____ and ______
TCP and UDP
ACK, URG, RST, SYN, PSH, and FIN are examples of what?
TCP header flags RST is reset. This means the TCP session will be reset/disconnected. It can be resumed via a new three-way handshake.
A ______ is an application that can serve as a basic firewall by restricting access to ports and resources based on user IDs or system IDs
TCP wrapper Using these is a form of port-based access control.
_______ is the most widely used communication protocol today
TCP/IP
The most widely used protocol suite is ______
TCP/IP. Based on open standards. Can be found in just about any operating system.
True or false: Other than the lower 0 - 1,023 ports being reserved for server use only, any other port can be used as a client source port as long as it is not already in use on that local system
True
True or False: There are 7 categories of UTP (Unshielded twisted pair)
True Cat 1 is voice only. Cat 7 is 10 gbps.
True or false: A potential security risk exists when non-IP protocols are used in a private network
True. Because they are rare, most firewalls are unable to perform packet header, address, or payload content filtering on those protocols.
True or False: No two devices can have the same MAC address in the same local Ethernet broadcast domain
True. Otherwise, an address conflict occurs. When duplicate MAC addresses occur, either the NIC hardware must be replaced or the MAC address must be modified (i.e. spoofed) to a nonconflicting alternative address.
_______ should be used only when the delivery of data is not essential. It is also often employed by real-time or streaming communications for audio and/or video
UDP
___________ technology (LAN) supports only a single communication to a specific recipient
Unicast
_________ is a simplex connection-less protocol
User Datagram Protocol
Secure Shell (SSH) and Internet Protocol Security (IPSec) are protocols used to establish ______
VPNs
TCP/IP can be secured using _________, which encrypts to add privacy, confidentiality, and authentication and to maintain data integrity.
Virtual private network (VPN) links between systems
________ is a new encryption scheme known as the Counter Mode with Cipher Block Chaining Message Authentication Code Protocol (CCMP), which is based on the AES encryption scheme.
WPA2
__________ technology (LAN) supports communications to multiple specific recipients
Multicast
The gateway (network device) works at which layer
(7) Application. Serves as a protocol translation tool. Further, application layer firewalls also operate at this layer.
_________ communications (LAN) rely on a timing or clocking mechanism based on either an independent clock or a time stamp embedded in the data stream, whereas _______ (LAN) communications rely on a stop and start delimiter bit to manage the transmission of data
(1) Synchronous, (2) Asynchronous
What are the three types of physical network connections?
(1) electrons over copper, (2) photons over fiber, or (3) radio signals through the air
SLIP, PPP, ARP, L2F, L2TP, PPTP, FDDI, ISDN are protocols of which OSI layer?
(2) Data Link
Switches and bridges operate at which OSI layer?
(2) Data Link layer
The ______ layer is responsible for formatting the packet (from layer above) into the proper format for transmission
(2) Data Link layer Only ethernet remains a common data link layer technology used in modern networks. The technology-specific protocols are in this layer to convert the packet into a frame.
Adding the hardware source and destination addresses occurs at which layer?
(2) Data link
ICMP, RIP, OSPF, BGP, IGMP, IP, IPSec, IPX, NAT, and SKIP are protocols of which OSI layer?
(3) Network
The Internet Protocol (IP) operates at which OSI layer?
(3) Network IP provides route addressing for data packets. Does not guarantee that packets will be delivered in the correct order, and not only once. Thus, TCP on IP must be employed to gain reliable and controlled communication sessions.
The _______ layer is responsible for adding routing and addressing information to the data
(3) Network layer This layer accepts the segment from the Transport layer and adds information to it to create a packet. The packet includes the source and destination IP addresses. Routing protocols are located at this layer (e.g. IPSec)
Routers and bridge routers are among the network hardware devices that function at which layer
(3) Network. Routers determine the best logical path for the transmission of packets based on speed, hops, preference, and so on.
SPX, SSL, TLS, TCP, and UDP are protocols of which OSI layer?
(4) Transport
The ________ layer is responsible for managing the integrity of a connection and controlling the session
(4) Transport It accepts a Protocol Data Unit (PDU), aka a container of information or data passed between network layers. A PDU coming from the session layer is converted into a segment.
The responsibility for verifying guaranteed delivery is at which layer?
(4) Transport The network layer is only responsible for providing routing or delivery information.
Transmission Control Protocol (TCP), Secure Sockets Layer (SSL), and Transport Layer Security (TLS) operate at which layer?
(4) Transport layer
The ________ layer controls how devices on the network are addressed or referenced
(4) Transport layer Establishes communication connections between nodes (e.g. devices) and defines the rules of a session. Session rules are established through a handshaking process, so that devices communicating agree on the rules.
The _______ layer establishes a logical connection between two devices and provides end-to-end services to ensure data delivery
(4) Transport layer Includes mechanisms for segmentation, sequencing, error checking, controlling the flow of data, error correction, multiplexing, and network service optimization.
NFS, SQL, and RPC are protocols of which OSI layer?
(5) Session
Structured Query Language (SQL), Network File System (NFS), and Remote Procedure Call (RPC) protocols operate at which layer?
(5) Session
The ________ layer is responsible for establishing, maintaining, and terminating communication sessions between two computers
(5) Session Manages dialogue discipline or dialog control (simplex, half-duplex, full-duplex), and establishes checkpoints for grouping and recovery.
The following encryption protocols and format types are indicative of which OSI layer? - ASCII, EBCDICM, TIFF, JPEG, MPEG, and MIDI
(6) Presentation
The ________ layer is responsible for transforming data received from the above layer into a format that any system following the OSI model can understand
(6) Presentation It imposes a common or standardized structure and formatting rules onto the data.
The ______ layer is responsible for encryption and compression
(6) Presentation Thus, it acts as an interface between the network and applications.
The ________ layer is what allows various applications to interact over a network, by ensuring that the data formats are supported by both systems.
(6) Presentation. Most file or data formats operate within this layer (eg. formate for images, sound, documents). For example, ASCII, JPEG, MIDI.
HTTP, FTP, LPD, SMTP, Telnet, TFTP, EDI, POP3, IMAP, SNMP, NNTP, S-RPC, and SET are protocols in which OSI layer?
(7) Application
Hypertext Transfer Protocol (HTTP), File Transfer Protocol (FTP), Simple Mail Transfer Protocol (SMTP), Telnet, Electronic Data Interchange (EDI), Simple Network Management Protocol (SNMP) protocols are located at this layer
(7) Application
The data stream is the message sent into the OSI protocol stack at which layer?
(7) Application IT retains this label until it reaches the Transport layer (4). Aka, it is a data stream for the top three OSI layers (7 - application, 6 - presentation, 5 - session).
The _______ layer determines whether a remote communication partner is available and accessible. It also ensures that sufficient resources are available to support the requested communications.
(7) Application The application is not located within this layer, rather the protocols and services required to transmit files, exchange messages, connect to remote terminals are found here.
The _______ layer is responsible for interfacing user applications, network services, or the operating system with the protocol stack
(7) Application. It allows applications to communicate with the protocol stack.
________ is used at the Data Link layer to resolve IP addresses into MAC addresses
ARP. Address Resolution Protocol. Traffic on a network segment is directed from its source system to its destination system using MAC address.
In the event that all packets of a transmission window were not received, no _________ is sent
Acknowledgement
_______ is used to resolve IP addresses into Media Access Control (MAC) addresses
Address Resolution Protocol (ARP) Traffic on a network segment (for example, cables across a hub) is directed from its source system to its destination system using MAC addresses.
_______ communications (LAN) occur with a continuous signal that varies in frequency, amplitude, phase, voltage, and so on
Analog
How does the TCP/IP Model Application layer map to the OSI Model?
Application, Presentation, and Session are the corresponding OSI layers
802.15 refers to which technology?
Bluetooth
_________ technology (LAN) supports communications to all possible recipients
Broadcast
STP, 10BastT (UTP), 10Base2 (thinnet), 10Base5 (thicknet), 100BaseT, 1000BaseT, and fiber-optic are examples of what?
Cabling types
_________ is the removal of header and footer as data moves up the OSI model layers
Deencapsulation
________ communications (LAN) occur through the use of a discontinuous electrical signal and a state change or on-off pulses
Digital Digital signals are more reliable than analog signals over long distances or when interference is present.
________ is not a specific mechanism for authentication; rather it is an authentication framework
EAP (Extensible Authentication Protocol) Effectively, EAP allows for new authentication technologies to be compatible with existing wireless or point-to-point connection technologies.
_________ is the addition of a header, and possibly a footer, to the data received by each layer from the layer above before it's handed off to the layer below
Encapsulation. As a message is encapsulated at each layer, the previous layer's header and payload combine to become the payload of the current layer.
What is the difference between using MAC addresses and EUI?
Extended Unique Identifiers looks for other types of hardware as well as software, while MAC addresses are typically used to identify only network hardware.
True or False: Ethernet is not the most common LAN technology
False. Ethernet is the most common LAN technology
__________ is a form of network data storage solution (i.e, SAN - storage area network) or NAS (network-attached storage) that allows for high-speed file transfers.
Fibre Channel
________ is used to encapsulate Fibre Channel communications over Ethernet networks
Fibre Channel over Ethernet (FCoE)
_________ is used to determine the health of a network or a specific link
Internet Control Message Protocol (ICMP). Utilized by ping, traceroute, pathping and other network management tools. Due to various denial of service attacks, ICMP traffic today is limited.
_________ allows systems to support multicasting, which is the transmission of data to multiple specific recipients.
Internet Group Management (IGMP).
_______ is a networking storage standard based on on IP. It is a converged protocol that allows location-dependent file services over traditional network technologies. It costs less than traditional Fibre Channel
Internet Small Computer System Interface (iSCSI)
Carrier-Sense Multiple Access (CSMA), Carrier-Sense Multiple Access with Collision (CSMA/CA), Carrier-Sense Multiple Access with Collision Detection (CSMA/CD) are all what?
LAN media access technologies that are used to avoid or prevent transmission collisions. Ethernet networks employ the CSMA/CD technology
________ is referred to as the hardware address
MAC address. Media Access Control address. 6-byte (48-bit) binary address written in hexadecimal notation. The first 3 bytes (24 bits) denote the vendor or manufacturer of the physical network interface (OUI). The last 3 bytes represent a unique number assigned to that interface by the same manufacturer.
How does the TCP/IP Model Internet layer map to the OSI Model?
Maps to the Network layer in OSI
The ________ layer manages error detection and node data traffic (e.g.) traffic control
Network layer
Intranet, extranet, and DMZ are examples of what?
Network segments/subnetworks. This is called network segmentation.
The _______ serves as an abstract framework, or theoretical model, for how protocols should function in an ideal world on ideal hardware
OSI model. Has become a common reference point against which all protocols can be compared and contrasted
The ________ protocol was developed to establish a common communication structure or standard for all computer systems
OSI. The actual protocol was not widely accepted, but the theory behind the OSI protocol, the OSI model, was readily accepted.
The ______ layer contains the device drivers that tell the protocol how to employ the hardware for the transmission and reception of bits
Physical
How does the TCP/IP Model Link layer map to the OSI model?
Physical and Data Link layers
At which layer is a message converted into electrical impulses that represent bits
Physical layer. Once sent from one computer, the receiving computer captures the bits from the physical connection and re-creates the message in the physical layer.
________ is the LAN media access technology that performs communications using a master slave configuration
Polling A primary system polls secondary systems whether they have a need to transmit data. It addresses collisions by attempting to prevent them from using a permission system. It is an inverse of CSMA/CA. Synchronous Data Link Control uses polling.
A _______ is little more than an address number that both ends of the communication link agree to use when transferring data within the transport layer
Port They allow an IP address to be able to support multiple simultaneous connections, each using a different port number.
A ________ is a set of rules and restrictions that define how data is transmitted over a network medium (e.g twisted-pair cable, wireless transmission)
Protocol
Ports 49,152 to 65,535 are known as __________
Random, dynamic, or ephemeral ports. These are used when negotiating a data transfer pipeline between client and server outside the initial service or registered ports
Ports 1,024 to 49,151 are known as ____________
Registered software ports. Ports that have one or more networking software products registered in order to provide standardized port-numbering system for clients attempting to connect their products.
What does a data stream become once it hits the Transport layer (layer 4)?
Segment (TCP protocols) or a datagram (User Datagram Protocol [UDP])
The first 1,024 ports are called ________
Service ports. These are standardized assignments as to the services they support. For example, port 80 is the standard port for web (HTTP) traffic, 23 is for Telnet, and 25 is for SMTP. These ports are reserved by servers and cannot by used as the source by a requesting client.
________ refers to one-way communication
Simplex. One of the control modes that communication sessions can operate in.
_________ is the process of investigating the presence, strength, and reach of wireless access points deployed in an environment
Site survey
The combination of an IP address and port number is known as a ________
Socket
What is the ultimate goal of the OSI model?
Supporting data exchange (e.g. network communication) between two computers
_____________ is the LAN media access technology that performs communications using a digital token
Token passing Possession of the token allows a host to transmit data.
_____ is a full-duplex connection-oriented protocol
Transmission Control Protocol (TCP). Connections between two systems are done using ports.
How does the TCP/IP Model Transport layer map to the OSI Model?
Transport
802.11 refers to which technology?
Wireless networking
What is the data called once it hits the Data Link layer (2)?
a Frame. Once the data hits the physical layer, it is converted into bits.
What is the data called once it hits the Network layer (3)?
a Packet