This answer is not selected as best answer. This answer may not be sufficient for exam.
Your limit has been exceed. We have implemented this system because, We got difficulty on managing our servers. Please donate some amount to remove this limit.
Quota: 0 / 30
Data Link Layer is second layer of OSI Layered Model. This layer is one of the most complicated layers and has complex functionalities and liabilities. Data link layer hides the details of underlying hardware and represents itself to upper layer as the medium to communicate.
Functionality of Data-link Layer
Data link layer does many tasks on behalf of upper layer. These are:
- FramingData-link layer takes packets from Network Layer and encapsulates them into Frames.Then, it sends each frame bit-by-bit on the hardware. At receiver’ end, data link layer picks up signals from hardware and assembles them into frames.
- AddressingData-link layer provides layer-2 hardware addressing mechanism. Hardware address is assumed to be unique on the link. It is encoded into hardware at the time of manufacturing.
- SynchronizationWhen data frames are sent on the link, both machines must be synchronized in order to transfer to take place.
- Error ControlSometimes signals may have encountered problem in transition and the bits are flipped.These errors are detected and attempted to recover actual data bits. It also provides error reporting mechanism to the sender.
- Flow ControlStations on same link may have different speed or capacity. Data-link layer ensures flow control that enables both machine to exchange data on same speed.
- Multi-AccessWhen host on the shared link tries to transfer the data, it has a high probability of collision. Data-link layer provides mechanism such as CSMA/CD to equip capability of accessing a shared media among multiple Systems.