北邮[高中]高级计算机网络课件Lan.pdfVIP

LAN Technologies Information Network Center Beijing University of Posts and Telecommunications 2013 1 Objectives ¡  Identify the position of data link layer in the OSI / rm structure. ¡  Identify and describe the basic operation of Ethernet and other LAN technologies. ¡  Describe how Ethernet and IEEE 802.3 nodes respond to congestion problems. ¡  Identify the types of physical connectors and cabling commonly used with different LANs. ¡  Identify the relationship of adjacent layers to DLL. ¡  Distinguish between the various versions of IEEE 802.3 implementations. ¡  Prospect the future of high speed LAN technologies. 2 Major topics ¡  LAN Protocol Architecture ¡  Standards ¡  Major Technology l  Ethernet/FastEthernet/GbE/10GbE l  Token Ring l  FDDI l  Wireless LAN ¡  Characteristics of LANs 3 Local Area Networks ¡  Optimized for a moderate size geographic area. ¡  All devices are attached to a shared medium. ¡  A transmission from any one device can be received by all other devices attached to the same network. ¡  Medium access control (MAC) protocols are required to arbitrates the access to the shared medium since only one station should be allowed to use the medium at a time. 4 LAN Protocol Architecture (IEEE 802 reference model) ¡  Architecture developed by IEEE 802 committee ¡  Lower layers of OSI model l  Physical l  Logical link control (LLC) l  Media access control (MAC)