Definition
Local Area Network (LAN)
A
local area network (LAN) is a group of computers and associated devices that
share a common communications line or wireless link. Major local area network
technologies are:
·
Ethernet
·
Token Ring
·
FDDI
Ethernet is by far the most
commonly used LAN technology. Typically, a suite of application programs can be
kept on the LAN server. Users can order printing and other services as needed
through applications run on the LAN server. A user can share files with others
at the LAN server; read and write access is maintained by a LAN administrator.
Ethernet
Ethernet is the most widely-installed
local area network ( LAN) technology. An Ethernet LAN typically uses coaxial cable or special grades of twisted pair wires. Ethernet is also used in wireless LANs. The most commonly
installed Ethernet systems are called 10BASE-T and provide transmission speeds up to
10 Mbps. 10-Gigabit Ethernet provides up to 10 billion bits per
second.
Token
Ring
The Token Ring protocol is the
second most widely-used protocol on local area networks after Ethernet. The
IBM Token Ring protocol led to a standard version, specified as IEEE 802.5. The
Fiber Distributed-Data Interface (FDDI) also uses a Token Ring protocol.
FDDI
(Fiber Distributed Data Interface)
The FDDI protocol is based on the token ring protocol. An FDDI network contains two
token rings, one for possible backup in case the primary ring fails. Work is
underway to connect FDDI networks to the developing Synchronous Optical Network
(SONET).
