Computer networks are defined by four factors which are as given below:

1) NETWORK SIZE:

According to the size of networks.

1) Local Area Network ( LAN)

2) Wide Area Network   (WAN)

In LAN network has the smaller area like a room a building or a floor.

In WAN, network has larger areas like countries & cities. Internet also is a Wide Area

Network.

WAN & LAN are compared by the speed of security, bandwidth and latency, billing, transmission, reliability, management and their standards.

2) NETWORK CONNECTIVITY:

Networks are also defined by connectivity in which two topologies are illustrated.

a) Point-to-Point

b) Broadcast

3) BY MEDIUM:

The types of networks is also based on the Medium of transmission.

Mediums of transmission are shown below:

• Copper wire
• Co-axial cable
• Optical fiber
• Radio waves

All these mediums different from each other with respect different parameters. These variables are speed of transmission, range of the transmitter and receiver computer, sharing of topology, information, installation & maintenance reliability and costs. The range of radio waves will be much more than an optical fiber wire. Similarly other mediums different from each other and appropriate medium is checked for the sake of transmission.

4) BY MOBILITY:

The networks are also divided according to their mobility.

In this respect there are two kinds of networks.

• Fixed networks
• Mobile networks

In these days mobile networks are the latest case. Mobile networks have been started in the last decade. In this regard there are some cause which are attached with the mobility of networks which are as given:

• tracking and Location
• Semi persistent connections
• Complex billing and administration as machines and users move around the network