LAN generally consists on the following components:
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x Workstation, such as personal computers, tablets, and smart phones. A network interface card (NIC) is needed for connecting any device or computer into a network. These cards are generally specific to the type of communication media used and the type of transmission technology being employed such as Ethernet for wire connection or Wi-Fi for the wireless connection.
x Server, which are the computers that store network software and/or shared files. Physically server is a powerful main computer in a network for information storage. On request this computer delivers data and programs/applications to clients. The data that hospital staff retrieves is not stored on individual computers, but on a central network computer called a server. All computers that have access to the server are called clients.
x Hub. As its name implies, a hub is a device in which data from a network come together. On a schematic a hub may appear as the box where all the Ethernet lines come together for a LAN or a segment of a LAN. Today single devices may serve as hubs and switches or even routers.
x Bridge. A bridge connects networks that use the same communication protocol. In the OSI reference model (Figure 7.4), a bridge operates at the data link layer, which is fairly low in the model, which means that it cannot translate signals between networks using different protocols.
x Gateway. A gateway can connect networks that have different communication protocols. These devices operate at the transport level of the OSI model, or higher.
x Switches, which serve as a collection point for the wires and wireless signal (WAP, wireless access point) that interconnect workstation on the network. A switch may either be a gateway or a router. In other words, it may operate at the router level or at a higher level. There are many types of switches available on the market today. All switches will route, or switch, data to their destination (Stair & Reynolds, 2003).
x Routers, which connect the LAN to a WAN or the Internet. Any LAN can be connected to the WAN or another LAN using router. A router operates at a higher level on the network layer of the OSI model. Routers are more sophisticated devices than bridges. Whereas bridges send on all data they receive, routers are able to help determine the actual destination of specific data.
x Connection Media, which are generally wires or wireless signals or a combination. Wireless signals require access point at interim locations throughout the network.