Network & Internet Tech - Final Exam

Which of the following are problems that TCP must overcome to ensure reliability? (choose all that apply)

- End systems might crash or reboot - Messages can be lost, duplicated, corrupted, delayed, or delivered out of order - Machines with faster hardware can generate data faster than slower ones can read and interpret said data causing the slower processor to be overrun. - Intermediate switches and router can be overrun with data from many aggressive hosts sending on a common link.

Complete the following categories of Packet Switched Networks:

- LAN: Local Area Network - MAN: Metropolitan Area Network - WAN: Wide Area Network

Which of the following statements are TRUE about bit/Byte stuffing?

- Once completed, it ensures the reserved characters do not appear in the payload. - Once used, the receiving end reverses the changes automatically - It allows for sequences of bits to be reserved for marking the beginning and end of the frame

- PAN: ______ Area Network - WLAN: ________ _________ Area Network - MAN: _______ Area Network - WAN: ________ Area Network

- Personal - Wireless Local - Metropolitan - Wide

What does a NIC do?

- Sends and receives frames - Calculates the CRC (used for error checking) - Recognizes addresses and frames

What are the steps of the Spanning Tree Protocol?

- Shortest path computation - Root Election - Forwarding

Which of the following are Header fields in an IPv4 datagram? (select all that apply)

- Time to Live (TTL) - Version - Destination IP - Header Length - Checksum - Total Length - Source IP

Match the Names with their Designations. A) Fast Ethernet B) Gigabit Ethernet C) Twisted Pair Ethernet D) Gig-E

A) 100BASE-T B) 1000BASE-T C) 10BASE-T D) 1000BASE-T

Match the following: A) Uses a translation table B)Network Address and Port Translation C) Network Address Translation D) Uses port number to associate each datagram with a specific "conversation" E) Replaces the IP source address when sending datagrams to the Internet F) Replaces the IP destination address when receiving datagrams from the Internet

A) NAT & NAPT B) NAPT C) NAT D) NAPT E) NAT & NAPT F) NAT & NAPT

What does DHCP stand for?

Dynamic Host Configuration Protocol

What does ICMP stand for?

Internet Control Message Protocol

Twisted pair Ethernet uses this type of connector.

RJ-45

Which sequence for the three-way handshake used to establish a TCP connection is correct?

SYN, SYN/ACK, ACK

A packet will be retransmitted indefinitely until it is received.

false

Application programs must be aware of the physical network they are using.

false

Each frame consists of two parts: The footer and the payload.

false

Ethernet devices and cabling has remained basically constant for over 30 years and new hardware is not compatible with older hardware.

false

IP is a guaranteed paradigm meaning that datagrams may be lost, duplicated, delayed, delivered out of order, or delivered with corrupted data.

false

In practice, all cells are the same size.

false

The acronym VLAN stands for Visual Local Area Network.

false

The best example of a packet switched network is the analog telephone system, also known and the "Public Switched Telephone Network" or "PSTN."

false

The header of a wireless frame can only have one destination MAC address.

false

The largest part of a frame is (usually) the header.

false

The original Ethernet was called thick net because the wires used to interconnect computers were heavy fiber cables. It was also called 10BASE5.

false

The size of an IP datagram is always the same.

false

There is one entry in every router for each host on the Internet.

false

Interference can be minimized if adjacent cells use different frequencies.

true

Most broadband providers provide their customers with a NAPT device that we commonly call our "router." In actuality it is usually a modem, router, NAT/NAPT, Wi-Fi access point all wrapped into one.

true

When a host is in range of two wireless access points, it must associate with a particular AP.

true

When one network has a MTU of 1500 and the next has an MTU of 1492 the router cannot re-encapsulate the first datagram to send over the second network.

true

Which of the following is a property of the circuit switched paradigm?

-Endpoint-to-endpoint communication -circuits are not permanent but created when needed and removed when communication ends -a single communication is not affected by others

In an ARP query, how many computers reply to the broadcast?

1

The third generation of Ethernet wiring was called twisted pair Ethernet and (at least physically) abandoned the bus model for a central interconnection called a hub which directly connected to each NIC.

true

Which of the following are true of a VLAN switch? (check all that apply)

VLAN switches allow one switch to act like multiple independent switches dividing computers into separate broadcast domains

Which of the following are designated as PRIVATE addresses and are non-routable?

- 169.254.0.0/16 - 10.0.0.0/8 - 192.168.0.0/16 - 172.16.0.0/12

Which of the following are true about adaptive bridges?

- A bridge examines the destination MAC address in a frame, and does not forward the frame onto the other LAN segment unless necessary. - Bridges "learn" which computers are connected to which port/segment by looking into the headers of incoming frames for MAC addresses. - They are sometimes also called learning bridges

Which of the following are wireless network technologies?

- Bluetooth - Wi-Fi routers at home - LTE cellular data network - Wi-Max used for mobile broadband

Which of the following are key features of WiMAX? (check all that apply)

- Can cover areas up to 10Km - Can provide transmission speeds of up to 70Mbps full-duplex at closer range - Allows for both Line-of-Sight (LOS) and Non-line-of-sight (NLOS) access.

Which of the following are features of UDP? (check all that apply)

- Can send or receive from many applications - Cannot guarantee delivery

Which of the following are features of TCP? (check all that apply)

- Delivered in order, and exactly as sent - A three way handshake must be used to establish a connection to a destination before sending data.

Which of the following are true about RFID? (check all that apply)

- Has limited distance - Used to "tag" items and devices for inventory control, and detection, and embedding digital data. - Short for Radio Frequency Identification

Which of the following are true about Infrared wireless technology? (check all that apply)

- Often used in remote controls - Signal reflects off objects and cannot not go through them. - Transmission is directional in a 30 degree cone - Transmission range and speeds vary considerably but typical applications are seen at rates up to 16Mbps and distances around 5m

Match Topology to the letter in the picture below:

- Star : C - Bus : A - Ring : B - Mesh : D

Which of the following are header fields for TCP?

- Window - Sequence number - Acknowledgement number - Source Port - Destination Port - Checksum

Complete the following Abbreviations: SYN: _____________ segment ACK: _____________ FIN: ________________ segment

- synchronization - acknowledgement - finished

In the following excerpt from a router forwarding table, which entry would apply to a packet with destination IP - 172.19.0.200: Remember: the MOST specific route that applies is the one used. 172.16.0.200/32 172.19.0.0/25 172.19.0.128/25 172.16.0.0/16 172.19.0.0/16 172.0.0.0/8

172.19.0.128/25

Put the following in order starting when a fully formed frame arrives at the first router. (Note the start point!!!) A) The frame is sent across the physical network. B) The router reads the IP datagram destination address from the header and calculates the new frame header (destination MAC address) using its ARP tables. C) The router encapsulates the datagram into the payload of a new frame D) The router de-encapsulates the frame and discards the old header information

A) 4 B) 2 C) 3 D) 1

Match the definitions with the features of UDP. A) Uses IP for transmission with no further steps to ensure transmission or correct errors. B) Applications do not need to set up or tear down a connection before sending data; it can be sent at any time. C) No state information is used or saved; No control messages are used. Data is the only element of the transmission. D) Does not divide up data into multiple packets or combine messages for delivery. E) Allows an individual application (not the host itself) to be an endpoint for communication. F) Can send 1-to-1, 1-to-many, many-to-1 or many-to-many. G) All the delivery problems of IP (messages can be lost, duplicated, delayed, corrupted or delivered out of order) still exist and are not detected or corrected.

A) Best-effort Delivery B) Connectionless Paradigm C) Connectionless Paradigm D) Message-Oriented Interface E) End-to-end Protocol F) Arbitrary Modes of Interaction G) Best-effort Delivery

Match the following PAN Technologies with their features or definitions: A) 802.15.1a B) 802.15.3a C) 802.15.4 D) Up to 721 Kbps @5m E) Uses 1 frequency band F) Uses 3 frequency bands G) Uses many frequency bands (spectrum) H) Used to replace cabling for peripherals I) Used for home automation and remote controlled devices

A) Bluetooth B) Ultra Wideband (UWB) C) ZigBee D) Bluetooth E) Bluetooth F) ZigBee G) Ultra Wideband (UWB) H) Bluetooth I) ZigBee

Match the definitions with the features of TCP. A) Applications must request a connection before sending data. B) Each connection has exactly 2 endpoints. C) Guaranteed delivery exactly as sent, complete and in order. D) Data can flow in either direction and from either side of the connection at any time. E) Sends a continuous sequence of data; Data is not grouped into messages or records. F) Sending application data size is not guaranteed during delivery. G) Applications reliably start a communication, ensures that all data has been delivered and then both sides agree to shut down the connection.

A) Connection Orientation B) Point-to-Point Communication C) Complete Reliability D) Full Duplex Communication E) Stream Interface F) Stream Interface G) Reliable Startup & Graceful Shutdown

Match the following: A) 01:00:5E:C0:00:08 B) 11111111.11111111.11111 C) One computer gets a copy of the packet D) 00-50-56-C0-00-08 E) Some computers get a copy of the packet F) All computers get a copy of the packet G) FF:FF:FF:FF:FF:FF

A) Multicast Address B) Broadcast Address C) Unicast Address D) Unicast Address E) Multicast Address F) Broadcast Address G) Broadcast Address

Match the following terms and descriptions: A) Organizationally Unique Identifier B) First 24-bits of a MAC address C) Network Interface Card D) Ethernet Address E) Media Access Control address F) Network Interface Controller G) 90:B1:1C:9B:3A:CC H) 48-bit unique address

A) OUI B) OUI C) NIC D) MAC Address E) MAC Address F) NIC G) MAC Address H) MAC Address

Match the term with its definition. A) Small blocks of data B) The basis of the Internet C) Uses Frequency Division Multiplexing D) Uses Statistical Multiplexing E) Uses Synchronous Time Division Multiplexing F) Varied in size depending on technology but commonly 1500 Bytes G) Can communicate with only one recipient H) Can communicate with one or many recipients I) Lower in cost due to the ability to share a single path

A) Packets B) Packet Switching C) Circuit Switching D) Packet Switching E) Circuit Switching F) Packets G) Circuit Switching H) Packet Switching I) Packet Switching

Match the following definitions and terms: A) When a subsequent packet is not sent until the previous packet is acknowledged. B) When a group of packets are sent (continuously) until acknowledgement of the first packet in the group arrives. C) When delivery of packets is delayed due to the limitations of the speed of a connection and the buffer of the intermediate systems. D) When TCP does to receive an acknowledgement within a specific amount of time, it sends the packet again.

A) Stop-and-go B) Sliding Window C) Congestion D) Retransmission

Two hosts communicating with each other directly without the use of an Access Point is called:

Ad hoc networking

Applications use logical port numbers that are independent of the OS to identify it as an endpoint.

false

Each subnet must have its own DHCP server.

false

There are two classes of WiMAX, Mobile (802.16e) and Fixed (802.16d): - Fixed WiMAX allows for hand-offs between access points and is used for Wireless broadband access to laptops and cell phones. - Mobile WiMAX doesn't allow for hand-offs and is used for wireless broadband connections to buildings and houses.

false

To handle packet lost, TCP uses negative acknowledgement with retransmission. Whenever a frame does not arrive, a small message is sent back to the sender reporting the failure.

false

To keep UDP short, there are no headers just data.

false

To prevent a cycle from causing an endless loop, bridges implement an algorithm that computes a Distributed Spanning Exchange. That is, the algorithm views bridges as nodes in a graph, and imposes a tree on the graph.

false

VLANs CANNOT operate across multiple switches.

false

Wireless WAN technologies can be divided into two categories, Cellular and Metropolitan communications systems.

false

IP routers use ________ to determine the next hop a packet will take.

forwarding tables

TCP and UDP function on this Layer of the Internet Model.

layer 4

The maximum amount of data a frame can send is called the Maximum Transmission Unit.

true

What is the term for using multiple frequencies to send data increasing performance and tolerating interference for wireless?

spread spectrum

The next upgrade to Ethernet wiring used a more skinnier more flexible coaxial cable and was called thin net or 10BASE2.

true

The size of each field of an IP header is always the same.

true

A bridged network is faster than a non-bridged one.

true

A communication mechanism with a dedicated path between two endpoints with guaranteed isolation is called circuit switching.

true

A hub is an analog device that forwards signals among (all) computers connected to it while a switch is a digital device that forwards packets to specific ports only.

true

A maximum length specification is a fundamental part of LAN technology.

true

A repeater is an analog hardware device used to extend a LAN. It amplifies and sends all incoming signals to the other side.

true

An IP datagram is encapsulated in the payload of a frame for transmission.

true

As a packet travels along a network path from router to router, the Source and Destination MAC address change from hop to hop but the Source and Destination IP do not.

true

As an IP datagram is sent over the Internet, the destination address in the header does not change.

true

Checksum field is optional in UDP.

true

Each UDP message must fit inside a single IP datagram. As a result of the fixed size of IP headers, and the common (and small) MTU, programmers typically limit UDP messages to prevent fragmentation.

true

For Ethernet, there are two types of cables, patch(or straight) and crossover (or crossed).

true

Hosts using IPv6 addresses don't use DHCP because they generates their own unique addresses using a multicast (broadcast) discovery of a network prefix and the MAC address (split) for the suffix.

true

IP lacks an important feature necessary for all applications; it cannot distinguish amongst different applications on a single host.

true

Ideally, each cell tower forms a hexagon because the cells can be arranged in a honeycomb. In practice, cellular coverage is not perfect and transmits in a circular pattern.

true

In a frame, the payload is transmitted second.

true

In the conventional Ethernet frame, the payload cannot be more than 1500 bytes; in the IEEE 802.3 standard, it cannot be more than 1492 bytes.

true

Mapping between a protocol address (IP address) and a hardware address (MAC address) is called address resolution.

true

Most wireless LANs are set up so hosts connect to an access point which is connected to a switch/router.

true

Network Hardware (NICs) do not understand IP addresses.

true

TCP provides a virtual connection between applications. This illusion of a physical connection is named as such because it is achieved through software.

true

TCP segments and UDP datagrams are encapsulated in IP packets which are encapsulated in network Frames and sent across the physical medium.

true

TCP uses the unreliable IP service to provide reliable data delivery.

true

The 16-bit type field allows for an Ethernet frame to be used with multiple protocols like IPv4 or IPv6.

true

The WiFi Alliance is a non-profit organization that certifies products based off of the IEEE 802.11 standard.

true

The government (FCC) regulates the frequencies in the electromagnetic spectrum that can be used for wireless communication.

true

To ensure that a particular user datagram was delivered to the intended host, UDP sometimes adds information from the IP layer like source IP and destination IP but this is only used to calculate a checksum, not for delivery itself. This is called a pseudo header.

true

To handle duplicate packets and out of order packets, TCP attached a sequencing number to each packet. If the packet is the next expected, it is passed up to the application, if not, it is catalogued and stored until it is ready to be used.

true

Two different types of access points exist, cheap dumb ones that rely on the computer to choose when to change their association and expensive intelligent ones that coordinate with each other to provide smooth handoffs.

true

UDP is the only connectionless transport protocol.

true

UDP would be a good protocol to use for live streaming radio.

true

When IPv4 addresses started to become scarce, Network Address Translation (NAT) was invented to allow multiple computers to share a single global address.

true

Wi-Fi stands for Wireless Fidelity.

true

To prevent a packet for one TCP session from being confused with a different session, a ______________ ID is added to each packet.

unique