Layer 2 Data Link

Question 1

True or false

Bit rate control can be found in layer 2

Answer 1

True

Question 2

What is layer 2 responsible for ?

Answer 2

Node - to - node data delivery

It receives data from network layer and passes it on to physical layer

In the process it creates frames and adds physical addresses

Question 3

What is error free transfer ?

Answer 3

Other layers can assume error free transfers

Question 4

What’s a checksum ?

Answer 4

It is a mathematical calculation that is applied to a chunk of data that says if you have this value and that value then it should add up to this other value

Question 5

What are the several functions happening in the Data link layer ?

Answer 5

Physical addressing known as MAC address

Frame traffic control, frame sequencing, frame acknowledgement
(which detects and revivers errors occurring at the physical layer)

Frame delimiting : identifying the start and end

Frame error checking (the checksum process)

Establishing and terminating links

Media access management
Meaning who is actually using the media at that time

Flow control
Error control
Access control

Question 6

What are the two sub layers of layer 2 ?

Answer 6

(LLC) logical link control

(MAC) media access control

Question 7

What is LLC ?

Answer 7

Logical link control

Thus provides and interface between the media access methods, which are down at the physical layer and the network layer protocols which are above it in layer 3

Question 8

What is MAC ?

Answer 8

Medium access control

Responsible for the connection to the physical media (gets it down to 1s & 0s)

Before it does it applies the MAC address
A 12 digit hexadecimal number

Question 9

Summarize data link layer

Answer 9

Layer 2 it is access to media and physical addressing