Local-area network interoperability

Several surveys have found that most large organisations, and many smaller ones, have installed more than one type of local-area network (LAN), usually a combination of Ethernet and token rings LANs and make use of several different types of protocol. Even when there is only one LAN and protocol. There are many circumstances where the engineering limitations must be overcome to extend the length of the network, to support an increased number of users and to improve the network´s performance. In each case the primary criterion is to ensure that the interconnected LANs provide the user with seamless interoperability. This interconnection is provided by the appropriate combination and use of repeaters, bridges, routers and gateways. Each of these relays has different capabilities and so it is important to choose the one best suited to the task in hand