Data Link Layer

What layer for Data Link Layer ?

• 1

• 2

• 3

• 4

Data link layer responsible for ?

• Ensure messages are delivered to the proper device on a LAN using hardware addresses.

• To establish logical connection between nodes.

• To start and stop traffic over the media.

• Responsible for the exchange of frame between nodes over a physical network media.

What the Data Link Sublayers

• CSMA

• LLC

• IEEE

• MAC

What Data link layer do ?

• Provides data delivery between Ethernet devices

• Connect upper layer processes to the physical layer

• Places data on and receives data from the network

• All of the above

What Media Access Control (MAC) do?

• Identifies the network protocol encapsulated in the data field

• Defines how packets are placed in the media

• Indicates congestion in the media.

• Determine logical topology – a signal path through physical topology

What Logical Link Control (LLC) do?

• Provide flow control

• Sequencing control bits

• Error notification

• Determine the 48-bits physical address

How many Data Link Layer function?

• 5

• 6

• 7

• 10

What Synchronization in data link layer function?

• Takes packets from network layer and encapsulates them into frame. Then send each frame bit by bit on the hardware.

• When data frames are send on the link, both machines must be synchronized in order to transfer to take place.

• Provides hardware addressing mechanism.

• Data link layer picks up signals from hardware and assembles them into frame.

How many Data link layer standards?

• 1

• 2

• 3

• 4

Data link frame have start and stop

• Yes

• No