Network protocols

A network protocol defines the rules and procedures in which data communication occurs among devices over a network. Without predefined rules or procedures, the messages traversing a network would be without any particular formatting and may not be meaningful to the recipient device. To further discuss the importance of having protocols on a network/system, we will use the following analogy to provide you with a real-world situation compared to network protocols.

Let's imagine you work for an organization, ACME Corporation, and within the company there are many policies and procedures that govern the handling of day-to-day transactions and activities within the organization. One of the most important procedures is the emergency evacuation plan. If there's an emergency within the organization, the procedure documents the rules and guidelines each employee must follow to ensure they are escorted safely out of the compound to the assembly point while the health and safety officers conduct their checks before allowing anyone to re-enter the compound. If proper procedures and guidelines didn't exist within ACME Corporation, people would be attempting to exit the compound in a haphazard manner, which may result in further safety issues. With procedures and guidelines, the employees would evacuate in a systematic manner.

This is the same concept that is applied to a network. There are many different protocols that use a network to communicate with another device. Each protocol has their own uniqueness in which the information is formatted and the rules and procedures it follows while traveling on the network until it is received by the intending recipient and process upward on the OSI reference model or the TCP/IP stack.

Now you have understand the concepts of network protocols, let's discuss some of the popular protocols with their respective port numbers and their importance on a network.