Computer Networking

A computer network can share the resources of one (or several) computer hard disk space and data devices. All material and software implemented is called network infrastructure. It distinguishes a network according to its structure, its size or its features and wiring topology connection.

According to Structure, a network can be either:

• peer to peer (P2P). In this case, the computers on the network share all their resources (data, peripherals). This type is easily configurable Win95, Win98, Millennium, or even Windows XP, but has no centralized administration.

• Client - Server. In client-server networks (also called heavy), one or more computers sharing resources with others is the network server. The other connected PCs (clients) use shared resources. The server can also be a Main-Frame. The operating system is dedicated: Windows NT, 2000 server, 2003, 2008, Novell NetWare or Linux. Client / server is primarily a concept of management software for databases network management.

In Windows systems, computers can be assembled into workgroup or in Domain Name Service (DNS) when using a server with 2003 or 2008 (also old 2000 and NT servers versions).

Type can be LAN (Local Area Network) for an internal compagny network, eventualy in Wireless (WLAN) or WAN (World Area Network). Contrary to current literature, the term is not limited to a distance, but the types of connections used. We can connect a LAN for a distance of 70 KM with no problems using right équipement and norme, even if the existing LANs are Ethernet with a limitation less than one kilometer in the most common cases (using repeaters).

Networking requires a physical connection between devices. It may consist of twisted pair (RJ45), coaxial cable, fiber optics, Electrical wiring (powerline) or Wireless. The type of connexion affects transmission speed, the maximum length of cable and the security of data transmitted. The communication between devices is governed by a Protocol and the method of communication (Ethernet is the most common LAN).

Advantages of using locally are as many data sharing between multiple devices and computers, centralized security, automated backups, Internet connection Sharing, ... but requires a more complex administration, particularly at user access rights, safety equipment (firewall, Tape Backup) ...

Related Definitions: OSI - DHCP server - web hosting -Token-ring

Ewuipments: Lan switch - Hub - server - router - Network Address Translation (NAT) - Blade - Rack