Protocols

There are several protocols including NetBeui, IPX and TCP/IP.

NetBeui (NetBios Extended User Interface) is a protocol that Microsoft has used heavily. It is designed for use on small networks.

IPX is Novell's networking protocol. Like NetBeui is is small and fast and can run with larger networks.

TCP/IP is the standard for internetworking. TCP/IP runs around multimultiple networks is has become the standard for networking. We will therefore concentrate on this prorocol, although all three potocols are similiar in many respects.

TCP/IP is involved with four of the seven layers that make up the OSI 7-layer Reference Model:

Link Layer Includes the device driver in the operating system

and the network interface card.

Network Layer Handles movement of packets around the network.

Transport Layer Provides flow of information between hosts, TCP/IP
protocol and UDP protocol

Application Layer Implements the application

When information is sent (a file, for example) TCP/IP adds a header to the front of the packet of bytes that constitutes the file. This heade, by definition the protocol, has several pieces of information in it. It includes version, type of service, total lenght, identification, flags, time to live, header checksum, source address, destination address, and options. The protocol takes up space at the beginning of the packet while traversing the network and is then taken off by the recieving computer.