Networks Protocols Part One

A network protocol is a set of rules for communicating between computers. Protocols govern format, timing, sequencing, and error control. Without these rules, the computer cannot make sense of the stream of incoming bits.

But there is more than just basic communication. Suppose you plan to send a file from one computer to another. You could simply send it all in one single string of data. Unfortunately, that would stop others from using the network for the entire time it takes to send the message. This would not be appreciated by the other users. Additionally, if an error occurred during the transmission, the entire file would have to be sent again. To resolve both of these problems, the file is broken into small pieces called packets and the packets are grouped in a certain fashion. This means that information must be added to tell the receiver where each group belongs in relation to others, but this is a minor issue. To further improve transmission reliability, timing information and error correcting information are added.

Because of this complexity, computer communication is broken down into steps. Each step has its own rules of operation and, consequently, its own protocol. These steps must be executed in a certain order, from the top down on transmission and from the bottom up on reception. Because of this hierarchical arrangement, the term protocol stack is often used to describe these steps. A protocol stack, therefore, is a set of rules for communication,...