-LAN LAN (Local Area Network) is a small region various communication devices connected together in a network, coverage generally confined to a room, building or Park. LAN features are: short distances, less delay, high data rate and transmission reliability.
Common types of network include: Ethernet (Ethernet), fiber distributed data interface (FDDI), asynchronous transfer mode (ATM), the token ring network (Token Ring), network Switching, their topology, transmission media, transmission rate, data format, there are many different aspects. Which is the most widely used Ethernet LAN-a bus structure, is the fastest and most economical network. We briefly on Ethernet (Ethernet), fiber distributed data interface (FDDI), asynchronous transfer mode (ATM) is introduced.
1, FDDI networks
Fiber Distributed data interface (FDDI) LAN technology is now mature a transmission. This transmission rate up to 100Mb/s network technology is based on the standard ANSIX3T9.5. The features of the network has timed token Protocol, supports a variety of topologies and transmission media for optical fiber. Using optical fiber as a transport media has many advantages:
1, a long transmission distance, maximum length up to 2KM between adjacent stations, the maximum distance between stations is 200KM.
2, has a larger bandwidth, FDDI bandwidth design for 100Mb/s.
3, with electromagnetic and radio frequency interference suppression capabilities during the transfer process is not under the influence of electromagnetic and radio frequency noise, does not affect the equipment.
4, fibre-prevents the transfer process was eavesdropping, also put an end to the waves of eavesdropping, which is the most secure transmission medium.
2, Ethernet, Ethernet
Ethernet is Xerox, and Digital Equipment and Intel LAN standard developed by the three companies, and first published in the early 80, called DIX1.0. 1982 modified versions to DIX2.0. The three companies to submit this specification for IEEE (Institute of electrical and electronic engineers) 802 Committee, after a member of the IEEE, and passed into the official IEEE standard, and numbered as IEEE802.3. Ethernet and IEEE802.3, although there are many different, the term Ethernet with 802.3 is generally considered compatible. IEEE 802.3 standards submitted to the International Organization for Standardization (ISO), the first joint technical Committee (JTC1), revised again became ISO8802.3.