What Is a Bit in Computer Networking?

A binary digit, or bit, is the smallest unit of data in computing. A bit represents one of two binary values, either a zero or a one. These values can also represent logic values such as On and Off or True and False. The unit of a bit is represented by a lowercase b. 

Bits in Networking

In networking, bits are encoded using electrical signals and pulses of light transferred through a computer network. Some network protocols, called bit-oriented protocols, send and receive data in the form of bit sequences. Examples of bit-oriented protocols include the point-to-point protocol.

Networking speeds are usually quoted in bits-per-second, For example, a speed of 100 megabits represents a data transfer rate of 100 million bits per second, which is expressed as 100 Mbps. 

Bits and Bytes

A byte is made up of eight bits in a sequence. You're probably familiar with a byte as a measure of file size or the amount of RAM in a computer. A byte can represent a letter, a number, a symbol, or other information a computer or program can use. Bytes are represented by an uppercase B.

Uses of Bits

Although they're sometimes written in decimal or byte form, network addresses like IP addresses and MAC addresses are ultimately represented as bits in network communications.

The color depth in display graphics is often measured in terms of bits. For example, monochrome images are one-bit images, while 8-bit images can represent 256 colors or gradients in grayscale. True color graphics are presented in 24-bit, 32-bit, and higher graphics.

Special digital numbers called keys are often used to encrypt data on computer networks. The length of these keys is expressed in terms of the number of bits. The greater the number of bits, the more effective that key is in protecting data. In wireless network security, for example, 40-bit WEP keys are relatively insecure, but 128-bit or larger WEP keys are much more effective.