Introduction of computer networks & Networking
In many ways networking is just another development ofdata communications, which began at the same time as computers themselves.
A computer network consists of a collection of computers, printers and other comunicative equipment that is connected together so that they can communicate with each other or in other word A network can be defined as a group of computers and other devicesconnected in some ways so as to be able to exchange data, resources, not only can you transfer files between them quickly and easily, but they can also share expensive resources like laser printers, hard disc arrays,backup tape drives, CD and DVD burners, scanners,internet connections and so on.
Components of a Network
- A minimum of at least 2 computers.
- Cables that connect the computers to each other, although wireless communication is becoming more common.
- A network interface device on each computer (NIC, Etharnet Card).
- Hubs for multicast the signals.
- A ‘Switch’ used to switch the data from one point to another.
- Network operating system software.
Basically there are two types of network configuration, peer-to-peer networks and client/server networks.
1.Peer-to-peer networks are more commonly implemented where there is less numbers of computers and where strict security is not necessary. All
computers have the same status, hence the term 'peer', and they communicate with each other on an equal footing. Files, such as word processing or spreadsheet documents, can be shared across the
network and all the computers on the network can share devices, such as printers, scanners, data etc which are connected to any one computer.
Advantages & Disadvantages:
- Easy to set up.
- Less expensive to install.
- Can be implemented on a wide range of operating systems.
- Very low levels of security supported or none at all.
- Limited Numbers of computers are used.
- Does not require a server.
- Demands a moderate level of skill to administer the network.
2.Client/server networks are more suitable for larger networks. A central computer, or 'server', acts as the storage location for files and applications shared on the network.The server also controls the network access of the other computers which are referred to as the 'client' computers.
Advantages & Disadvantages:
- More difficult to set up.
- More expensive to install.
- A variety of operating systems can be supported on the client computers, but the server needs to run an operating system that supports networking.
- High levels of security are supported, all of which are controlled from the server. Such measures prevent the deletion of essential system files or the changing of settings.
- No limit to the number of computers that can be supported by the network.
- Requires a server running a server operating system.
- Demands that the network administrator has a high level of IT skills with a good working knowledge of a server operating system.