Introduction to Networking
In a Nutshell - CIW Course Section 1, Part C, Chapter 1
A network is two or more connected computers that share data. This may be in a small office or may encompass millions of computers around the globe using the Internet. Networking with the Internet is known as Internetworking.
Mainframes are discussed briefly, as while still very much in use they are likely to be phased out relatively quickly in favour of smaller computers in a client/server relationship. The client/server model is also referred to as distributed computing as the processing is shared between the client and the server. This is not a one-to-one relationship. One server may serve many clients and one client may communicate with several servers.
A network may be a server based network, where a number of clients access resource from one or more servers, or it may be a simple peer-to-per network where a number of workstations are connected and share each other's resources. The latter, is generally, suitable for a small office only.
A network consists of three basic elements: Protocols, Transmission Media and Network Services. Two basic types of network exits: peer-to-peer and server based.
A network topology describes the manner in which computers, or nodes, are interconnected.
Bus Topology. Advantages: Simple, Inexpensive and easy to operate. Disadvantages: A fault can break the whole network. Identifying problems is difficult.
Star Topology. Advantages: Expansion and reconfiguration are simple. Disadvantages: Single point of failure.
Ring Topology. Advantages: Works well with heavy traffic. Disadvantages: Expansion is difficult.
Mesh Topology. Advantages: No single point of failure. Disadvantages: Complex and expensive.
Network Operating Systems
The most popular network operating systems include: Novell Netware, Microsoft Windows NT and Microsoft Windows 2000, Linux and UNIX. The network operating system (NOS) is responsible for managing resources on the network including managing multiple users, providing access to file and print services and network security.