Communication SystemCommunication focuses on the hardware (devices) and protocols, essential for network communication. The hardware includes network devices such as switches, network cards, hubs, etc. The protocol that used most extensively and efficiently these days is Ethernet protocol. This protocol works for the Ethernet standards such as Ethernet cards and Ethernet switches. Moreover the issues associated with WANs (wide area networks) and LANs (local area networks) such as cost, performance, area, and hardware requirements are also covered. Overall network communication can be divided into two categories. · Communication Controller · Communication Server The communication controller handles client / server activities. The other is communication server that manages user interactive functionalities.

Communication Controller

Communication Controller is the Input / Output manager between clients and server, within a computer network. A communication controller unit may consist of bridges, routers, repeaters, multiplexors, interface cards and converters, interface adapters, and / or media converters. The controller unit assures control functions such as data security, error checking, information collection and routing, data transmission (parallel / serial), etc.

Front-End Processor

A communication controller is a separate device from client / servers and thus manages all the external input / output it self. This not only relieves the load of work from the clients but also increases the processing. Therefore a Communication Controller Unit is sometimes referred to as front-end processor.

Industrial Controllers

At industrial level industrial compatible controllers are also available as industrial controllers. Mostly these controllers are based on Ethernet protocol, an internal processor, interfaces (usually serial), RAM, Flash memories, and some output / input interfaces providing compatibility with other devices and computers.

Communication Server

A communication server is an embedded system that offers the communication services to the users on the network. The services include the channel distribution to the users. The communication server allows or disallows the users number of channels to access or transmit information. Besides information access, a communication server is also involved in gateway functions, which provide connections to the clients or host computers for data sharing. Moreover communication server also involves in Modem, Routers & bridge functions, and in E-mail services.

Network Equipment

Network equipment allows the communication within the network providing data integrity, data security, and data reliability. A computer network is comprised of number of devices most importantly containing: · Network Repeaters · Network Gateways · Network Hubs and Switches · Network Converters · Network Adapters · Network Bridges · Network Routers