What is protocol in data communication? Explain with an example.
A protocol in data communication is a set of standard rules that the communicating parties — the sender, the receiver, and all other intermediate devices — need to follow for successful and reliable data communication. Since the sender and receiver can be in different networks with varying data transfer rates, protocols ensure proper communication.
Protocols handle flow control, access control, and addressing. They define how computers identify each other, the data format for transit, and ensure all data reaches the destination without loss.
For example, HTTP (HyperText Transfer Protocol) is the primary protocol used to access the World Wide Web. Another example is FTP (File Transfer Protocol), which is used for transferring files from one machine to another using a client-server model.
Explanation
The answer draws directly from Section 11.8 of the textbook which defines protocol as 'a set of standard rules that the communicating parties — the sender, the receiver, and all other intermediate devices need to follow.' The explanation of flow control and the examples of HTTP and FTP are all explicitly mentioned in the provided context. The answer meets the 3-mark requirement by defining the concept, explaining its purpose, and providing a concrete example.