ITEE ITEE-1 | Page 266

(1)LAN topologies The type of connection for a LAN is called a “topology.” The three types of LAN topologies are summarized below. Topology Bus Star Ring Advantages Drawbacks Computers and peripherals branch off from and connect to a single transmission path called a “bus.” A failure with a computer has few ramifications on the network. Difficult to identify the point of failure. Cost of building this type of network is relatively high. Computers and peripherals radially branch out from and connect to line concentration devices such as hubs. Easy to add and move computers. A failure with a hub or other line concentration device stops the entire network. Computers and peripherals are connected by a ring-shaped transmission path. Easy to identify the point of failure. A failure with even a single computer or transmission path stops the entire network. The cost of building this type of network is relatively high. Star Hub Refer to “Chapter 9-4-1 2 (3) LAN components.” Reference Transmission path A “transmission path” is a path used for data communication. The width of the transmission path determines the amount of information that can be exchanged. Technology element Bus Reference Chapter 9 Description Ring (2)LAN standards There are various standards for LANs, each specifying a certain type of cable, topology, and access control. “Ethernet” is a typical LAN standard. ●Ethernet “Ethernet” is the most popular international standard specification for LANs. “Ethernet” was jointly developed by DEC, Intel, and Xerox, and was later improved by the IEEE 802.3 Committee. It has now become an international standard specification. 260