Thread: Wide Area Network

A wide area connection is a voice, data or video network that provides connections from one of more computers or network within buildings or college campus to one or more computers or networks that are external to such buildings or college campus. The network within a building or college campus is know as LAN and WAN which is wide area or we can say that WAN connects two or more LANS because LAN network in two different buildings can not communicate with each other. All these LANs area connected either through telephone lines, data cables or through satellites for the WAN network. The largest WAN in existence is the internet and internet is most com'mon in conventional life and connect users at large geographic area.

WAN protocols

WAN technology functions at the lower three layers of the OSl reference model i.e physical layer ,data link layer, network layer and communication among these layers is possible through protocols. Protocols are nothing but set of rules. All the layers uses same or different types of devices and protocol standards are use to initiate and maintain communication b/w these devices. Dissimilar set of devices required strict set of communication standards. As we know that their are number of protocols and all are incompatible to communicate with one another so WAN make it possible.

Network Architecture

When networks are designed proper protocols are chosen and packed with hardware and software. The collection of protocols, hardware and software is known as the network architecture. Most widely used is System Network Architecture developed by IBM.

WAN Hardware

Physical devices which are used on the communication networks are dependent on one another or we can say, that they cooperate with each other. With this cooperation many network problems like data exchange between components, network management etc become easier. Different types of hardware devices used in WAN are as follows:

• Host:

host is the machine on which all the application programs and database management are performed by the user.

•Front end processors:

In order to perform most of the I/O operation for the host front end processors are used. It is placed between terminals and host and this enables the host to work almost exclusively on data processing tasks

• Controllers:

Controllers controls all the activities performed by hardware and software components. So it gives relieve to the host CPU from communication burden and prevent from traffic. It can be used within any type of network topology such as hierarchical, bus, ring and star.

• Protocol Converters:

Wide area network uses different type of protocols often composed of a mixture of many types of computers. Different type of protocols based system components can not communicate directly so to enable diverse system components to communicate with one another and to operate as a functional unit a protocol converter is required.

• Multiplexers:

Multiplexers accepts data from several terminals and transmit it over very high speed channels connected to the host. Terminals from which multiplexer accept data can be used low speed data channels or high speed data channels.
Multiplexers enable several low speed devices to .share the same high speed line. Different types so multiplexers are used so that signal, that are combine at one end can be store out on the other end.

• Gateways & Bridges:

both provide facilities that enable the devices of one network to communicate with the devices of another networks. the difference between gateways and bridges is that gateways can be connect to networks which have totely different communication architectures on the other hand bridges connects the networks which have the same communication architecture.



Virtual private network

As we know W AN is the group of interconnected LAN networks and all are connected through the high speed data cables, leased telephone lines or satellites. Because all are connected through data lines so that unauthorized group can not access this network Virtual private network provide access to private networks that an unauthorized group can access the network. Virtual private network is a remote computer connecting to a remote network over an intermediate network such as the internet or LAN. Once connected, user can make use of network devices as if they were directly connected to the network.

Backbone Network

buildings, in different buildings, in campus environment or over wide area networks. Web technology is most popular and commonly used in conventional life so that more traffic is flowing through the backbone and this traffic is handle itself by backbone networks. Distinct LANs are tie together by distributed backbones. A backbone is a larger transmission line that carriers data gathered from smaller lines that interconnected with it.

• The local area networks are connect to for a wide area networks through the set of lines known as backbone to span distance efficiently.

• A backbone is a set of patr,s that a local or regional network connect to for long-distance interconnection on the internet or other wide area network.
Backbone network is a technology which is used to connect the different types of networks in the same