Functionality of llc and mac

GATE_LEARNER 2017-10-16 14:28:05 UTC #1

In data link layer which are all the functions performed by MAC sub layer and which are all the functions performed by Logical link layer ??
1)framing
2)error control
3)flow control
4)access control
5)physical addressing

Ruturaj 2017-10-16 14:41:27 UTC #2

Logical Link Control - Flow control, Error Control

MAC - Framing, Access Control, Error Control, Physical Addressing

You can remember it like this -> Except Flow control MAC does everything.

GATE_LEARNER 2017-10-16 14:53:45 UTC #3

llc dont do error control i guess

Ruturaj 2017-10-16 14:56:11 UTC #4

See 1st paragraph Last Line.

Ruturaj 2017-10-16 14:59:33 UTC #5

You can refer this also. Page 1/7

http://seat.massey.ac.nz/159334/Lectures/Week2_3_1s.pdf

GATE_LEARNER 2017-10-16 15:00:07 UTC #6

it provide management not control… it provides reliability i agree…

see here
http://computernetworkingsimplified.in/data-link-layer/components-data-link-layer-llc-mac/

Ruturaj 2017-10-16 15:06:24 UTC #7

Always read from authentic sources. Either from nptel or foreign university materials…

http://nptel.ac.in/courses/106105080/pdf/M5L3.pdf

read page 4.

GATE_LEARNER 2017-10-16 15:10:30 UTC #8

hehe i agree… well the link http://seat.massey.ac.nz/159334/Lectures/Week2_3_1s.pdf say a part of framing also provided at llc… what does it mean

Ruturaj 2017-10-16 15:17:35 UTC #9

The 802.1 sublayer gives an introduction to set of standards and gives the details of
the interface primitives. It provides relationship between the OSI model and the 802
standards. The 802.2 sublayer describes the LLC (logical link layer), which is the upper
part of the data link layer. LLC facilitate error control and flow control for reliable
communication. It appends a header containing sequence number and acknowledgement
number. And offers the following three types of services:

Read page 4 from that nptel slide. The above highlighted sentence says it all. This is the part of framing that LLC performs. But it is optional because all times we dont need sequence and acknowledgement number.

Harsha_1997 2017-11-20 13:36:30 UTC #10

The MAC is primarily responsible for:
*framing
*deframing
*collision resolution.
*control of access to the physical transmission medium.
*addressing of destination stations(both as induvidual stations and as groups of stations)

but as per the given options the function performed by MAC sub layer are options:
1)FRAMING.
4)ACCESS CONTROL
5)PHYSICAL ADDRESSING.

The primary functions of Logical link layer are:
*flow control
*multiplexing
*error control

but as per given options the functions performed by LLC are
options:
2)ERROR CONTROL
3)FLOW CONTROL.