Chapters 13 and 15

Question 1

Role and Purpose of Data Link Layer:

Answer 1

Protocols in the data link layer specify communication over a single network

More precisely, how neighboring computers on the same network send and receive data

Question 2

Network Protocol Specifications for the Data Link Layer Include:

Answer 2

Packet switching

Hardware addressing using MAC addresses

Method of access to the transmission medium (wire or air)

What is the max size of a packet that the network supports?

Question 3

LAN

Answer 3

Local Area network, spans room or building

Question 4

WAN

Answer 4

Wide Area Network:: spans sites in multiple cities

Question 5

Multi-access networks

Answer 5

organized in a way such that multiple computers share the same medium

LANs are these

Question 6

Bus Topology

Answer 6

all computes attach to a single cable

Question 7

Ring Topology

Answer 7

computers are connected in a closed loop

Question 8

Star Topology

Answer 8

computers connect to a central “hub”

Question 9

Mesh Topology

Answer 9

direct cable between any two computers (rare)

Question 10

MAC Address (also called hardware address)

Answer 10

In order for packets to reach the correct recipient, each computer must have a unique identifier

Question 11

Network Interface Card (NIC)

Answer 11

(I/O) device that allows for a computer to be connected to a network

Question 12

T or F: hardware (MAC) addresses are used only on the local network (LAN) by the data link (network) layer protocols

Answer 12

True

Question 13

MAC addressed are used to route packets within a…

Answer 13

LAN

Question 14

IP addresses are used to route packets across…

Answer 14

different networks (on the internet)

Question 15

of bits for a MAC address

Answer 15

48 bits and is commonly written using hexadecimal values

EX) 78:2b:cb:b6:79:20

Question 16

of bits for a IPv4 address

Answer 16

32 bits and is commonly written using decimal values (0-255)

EX) 147.53.55.223

Question 17

of bits for a IPv6 addresses

Answer 17

126 bits = 16 bytes

Question 18

Packet Switching vs Circuit Switching

Answer 18

Packet switching: no dedicated line and can be asynchronous

Circuit Switching: must establish a dedicated line and communicates synchronously (must be on at the same time)

Question 19

Unicast

Answer 19

uniquely identifies destination on computer

Question 20

Multicast

Answer 20

subset of computers on LAN to receive frame

Question 21

Broadcast

Answer 21

all computers on LAN are to receive the frame

Question 22

Frame

Answer 22

Data Link Layer Header + Payload

basic transmission unit at the data link layer

Question 23

MAC addresses are used…

Answer 23

within a LAN

Question 24

IP addresses are used…

Answer 24

across LANs

Question 25

promiscuous mode

Answer 25

allows a station to receive all frames regardless of address