3Com 3C892 manual Networking Primer, Example of a LAN

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NETWORKING PRIMER

This chapter provides a description of basic networking concepts and terminology to help you better understand the key functionality of the ISDN LAN Modem.

What is a network? A network is a set of computers and other devices such as printers, modems, and scanners that are connected together either directly via physical cables or indirectly via dial-up telephone services. A network can be in the same room, the same building covering a local area, or geographically dispersed covering a wide area.

What is a LAN? A Local Area Network (LAN) is two or more computers linked together in a contained location such as an office building. By linking the computer together, and creating a LAN, users can share files and share access to printers.

To physically create a LAN, each computer must be linked together using some type of cabling. Typically, Ethernet cabling is used. There are three main types of Ethernet networks: 10BASE-T, 10BASE-2 and 10BASE-5. The ISDN LAN Modem supports four 10BASE-T connections.

A 10BASE-T Ethernet network is used in small networks with only a few dozen devices closely located. The physical connection for a 10BASE-T Ethernet network is over a twisted pair cable. The connector used for 10BASE-T looks similar to the connector used for your telephone. A 10BASE-5 Ethernet network is used in large networks with many devices where transmissions occur over distant geographic areas. A 10BASE-2 (Thin) Ethernet network is used in smaller networks with all devices being relatively close together.

10 Mbps Ethernet LAN

Figure 53 Example of a LAN

What is a WAN? A Wide Area Network is the result of the connection of two or more LANs, typically using dial up telephone services via a modem and usually over far geographic distances.