Changes

A '''local area network''' ('''LAN''') is a [[computer network]] covering a local area, like a home, office, or group of buildings. Current LANs are most likely to be based on switched [[IEEE 802.3]] [[Ethernet]] running at 10, 100 or 1,000 [[Megabit per second|Mbit/s]] or on [[Wi-Fi]] technology .  

A '''local area network''' ('''LAN''') is a computer [[network]] covering a local area, like a home, office, or group of buildings. Current LANs are most likely to be based on switched [[IEEE 802.3]] [[Ethernet]] running at 10, 100 or 1,000 [[Megabit per second|Mbit/s]], or on [[Wi-Fi]] technology.  

The defining characteristics of LANs in contrast to [[Wide area network|WAN]]s (wide area networks) are: their much higher data rates; smaller geographic range; and that they do not require leased telecommunication lines.

The defining characteristics of LANs in contrast to [[Wide area network|WAN]]s (wide area networks) are their much smaller geographic ranges, higher throughput, and their independence of leased telecommunication lines.

==Technical aspects==

==Technical aspects==

 

Although switched Ethernet is now most common at the [[physical layer|physical]] and [[data link layer|data link]] layers, and [[TCP/IP]] as a [[Communications protocol|protocol]], historically many different options have been used (see below), and some continue to be popular in niche areas.  Larger LANs may have redundant links, and [[router]]s or switches capable of using [[spanning tree protocol]] and similar techniques to recover from failed links. LANs may have connections to other LANs via routers and leased lines to create a WAN ([[Wide Area Network]]). Most will also have connections to the large public network known as the [[Internet]], and links to other LANs can be 'tunneled' across this using [[VPN]] technologies.

Although switched Ethernet is now most common at the [[physical layer|physical]] and [[data link layer|data link]] layers, and [[TCP/IP]] as a [[Communications protocol|protocol]], historically many different options have been used (see below), and some continue to be popular in niche areas.  Larger LANs may have redundant links, and [[router]]s or switches capable of using [[spanning tree protocol]] and similar techniques to recover from failed links. LANs may have connections to other LANs via routers and leased lines to create a WAN ([[Wide Area Network]]). Most will also have connections to the large public network known as the [[Internet]], and links to other LANs can be 'tunnelled' across this using [[VPN]] technologies.

==History==

==History==

In the days before personal computers, a site might have just one central computer, with users accessing this via [[computer terminal]]s over simple low-speed cabling. Networks such as IBM's SNA ([[Systems Network Architecture]]) were aimed at linking terminals or other mainframes at remote sites over leased lines—hence these were wide area networks.  

In the days before personal computers, a site might have just one central computer, with users accessing this via [[computer terminal]]s over simple low-speed cabling. Networks such as IBM's SNA ([[Systems Network Architecture]]) were aimed at linking terminals or other mainframes at remote sites over leased lines—hence these were wide area networks.  

Of the competitors to NetWare, only [[Banyan Vines]] had comparable technical strengths, but Banyan never gained a secure base. [[Microsoft]] and [[3Com]] worked together to create a simple network operating system which formed the base of 3Com's 3+Share, Microsoft's [[LAN Manager]] and IBM's [[LAN Server]]. None of these were particularly successful.

Of the competitors to NetWare, only [[Banyan Vines]] had comparable technical strengths, but Banyan never gained a secure base. [[Microsoft]] and [[3Com]] worked together to create a simple network operating system which formed the base of 3Com's 3+Share, Microsoft's [[LAN Manager]] and IBM's [[LAN Server]]. None of these were particularly successful.

In this same timeframe [[Unix]] [[workstations|computer workstation]] from vendors such as [[Sun Microsystems]], [[Hewlett-Packard]], [[Silicon Graphics]], [[Intergraph]], [[NeXT]] and [[Apollo Computers|Apollo]] were using [[TCP/IP]] based networking. Although this market segment is now much reduced, the technologies developed in this area continue to be influential on the Internet and in both [[Linux]] and Apple [[Mac OS X]] networking, and the TCP/IP protocol has now almost completely replaced [[IPX]], [[AppleTalk]], [[NETBEUI]] and other protocols used by the early PC LANs.

In this same timeframe [[Unix]] [[workstations|computer workstation]]s from vendors such as [[Sun Microsystems]], [[Hewlett-Packard]], [[Silicon Graphics]], [[Intergraph]], [[NeXT]] and [[Apollo Computers|Apollo]] were using [[TCP/IP]] based networking. Although this market segment is now much reduced, the technologies developed in this area continue to be influential on the Internet and in both [[Linux]] and Apple [[Mac OS X]] networking, and the TCP/IP protocol has now almost completely replaced [[IPX]], [[AppleTalk]], [[NETBEUI]] and other protocols used by the early PC LANs.

== See also ==

== See also ==

*[[Metropolitan Area Network|MAN]]

*[[Metropolitan Area Network|MAN]]

[[Category:Telecommunications]]

[[Category:Telecommunications]]