Local area network
The LAN contrasts the wide area network (WAN), which not only covers a larger geographic distance, but also generally involves leased telecommunication circuits or Internet links.
This medium provides physical connectivity between the Ethernet interfaces present on a large number of IP-aware devices.
Wireless networks have become popular in residences and small businesses because of their ease of installation, convenience, and flexibility.
Advanced LANs are characterized by their use of redundant links with switches using the spanning tree protocol to prevent loops, their ability to manage differing traffic types via quality of service (QoS), and their ability to segregate traffic with VLANs.
Wireless LAN (WLAN) also has its topologies: independent basic service set (IBSS, an ad-hoc network) where each node connects directly to each other (this is also standardized as Wi-Fi Direct), or basic service set (BSS, an infrastructure network that uses an wireless access point).
These would additionally make use of telephone wires such as VDSL and VDSL2, coaxial cables, or fiber to the home for running fiber-optic cables directly into a house or office building, or alternatively a cellular modem or satellite dish in the latter non-fixed cases.
A gateway establishes physical and data link layer connectivity to a WAN over a service provider's native telecommunications infrastructure.
Such devices typically contain a cable, DSL, or optical modem bound to a network interface controller for Ethernet.
Home and small business class routers are often incorporated into these devices for additional convenience, and they often also have integrated wireless access point and 4-port Ethernet switch.
A 1970 report from the Lawrence Radiation Laboratory detailing the growth of their "Octopus" network gave a good indication of the situation.
[dubious – discuss] It used 10 kilometers of simple unshielded twisted pair category 3 cable—the same cable used for telephone systems—installed inside the benches of the European Parliament Hemicycles in Strasbourg and Luxembourg.
[22][23][24] In practice, the concept was marred by the proliferation of incompatible physical layer and network protocol implementations, and a plethora of methods of sharing resources.
A solution appeared with the advent of Novell NetWare which provided even-handed support for dozens of competing card and cable types, and a much more sophisticated operating system than most of its competitors.
None of these enjoyed any lasting success; Netware dominated the personal computer LAN business from early after its introduction in 1983 until the mid-1990s when Microsoft introduced Windows NT.
Econet was Acorn Computers's low-cost local area network system, intended for use by schools and small businesses.
By 1994, vendors included Cisco Systems, National Semiconductor, Network Peripherals, SysKonnect (acquired by Marvell Technology Group), and 3Com.
