Each layer has its own set of protocols a particular

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: er communication networks. These rules provide a method for orderly and efficient exchange of data between the sender and the receiver and for the proper interpretation of controls and data transmitted as raw bits and bytes. These rules are embedded in the data communication software. Roles of a Communication Protocol In any computer network, a communication protocol normally performs the following functions for the efficient and error-free transmission of data. It has a separate set of rules (implemented in software) for performing each of these functions. 1. Data sequencing. It refers to breaking a long message into smaller packets of fixed size. Data sequencing rules define the method of numbering (or sequencing) packets to detect loss or duplication of packets, and to correctly identify packets that belong to the same message. 2. Data routing. Routing algorithms are designed to find the most efficient paths between a source and a destination. They can handle varying degree of traffic on the present network configuration with optimal time utilization. 3. Data formatting. Data formatting rules define which group of bits or characters within a packet constitutes data, control, addressing, or other information. 4. Flow control. A communication protocol also prevents a fast sender from overwhelming a slow receiver. It ensures resource sharing and protection against traffic congestion by regulating the flow of data on the communication lines. 5. Error control. These rules are designed to detect errors in messages and to ensure transmission of correct messages. The most common method for correcting errors is to retransmit the erroneous message block. This method requires coordination between the sender and the receiver nodes so that the block having error is discarded by the receiver node and is retransmitted by the sender node. 6. Precedence and order of transmission. These rules condition all nodes about when to transmit their data and when to receive data from other nodes. It is ensured that all nodes get a chance to use the communication lines a...
View Full Document

This document was uploaded on 04/07/2014.

Ask a homework question - tutors are online