What is a Network, I mean computer Network?

The first task in understanding how to build a computer network is defining what a network is and understanding how it is used to help a business meet its objectives. A network is a connected collection of devices and end systems, such as computers and servers, that can communicate with each other.

Networks carry data in many types of environments, including homes, small businesses, and large enterprises. In a large enterprise, a number of locations might need to communicate with each other, and you can describe those locations as follows:

■ Main office: A main office is a site where everyone is connected via a network and where the bulk of corporate information is located. A main office can have hundreds or even thousands of people who depend on network access to do their jobs. A main office might use several connected networks, which can span many floors in an office building or cover a campus that contains several buildings.

■ Remote locations: A variety of remote access locations use networks to connect to the main office or to each other.

— Branch offices: In branch offices, smaller groups of people work and communicate with each other via a network. Although some corporate information might be stored at a branch office, it is more likely that branch offices have local network resources, such as printers, but must access information directly from the main office.

— Home offices: When individuals work from home, the location is called a home office. Home office workers often require on-demand connections to the main or branch offices to access information or to use network resources such as file servers.

— Mobile users: Mobile users connect to the main office network while at the main office, at the branch office, or traveling. The network access needs of mobile users are based on where the mobile users are located.