Желілік байланыс үшін NetBIOS API

API allowing applications on separate computers to communicate over LAN via the session layer

NetBIOS ('/n//ɛ//t//b//aɪ//ɒ//s/) is an acronym for Network Basic Input/Output System. It provides services related to the session layer of the OSI model allowing applications on separate computers to communicate over a local area network. As strictly an API, NetBIOS is not a networking protocol. Operating systems of the 1980s (DOS and Novell Netware primarily) ran NetBIOS over IEEE 802.2 and IPX/SPX using the NetBIOS Frames (NBF) and NetBIOS over IPX/SPX (NBX) protocols, respectively. In modern networks, NetBIOS normally runs over TCP/IP via the NetBIOS over TCP/IP (NBT) protocol. NetBIOS is also used for identifying system names in TCP/IP (Windows). Simply stated, it is a protocol that allows communication of data for files and printers through the Session Layer of the OSI Model in a LAN.

NetBIOS is an operating system level API that allows applications on computers to communicate with one another over a local area network (LAN). The API was created in 1983 by Sytek Inc. for software communication over IBM PC Network LAN technology. In 1985, IBM went forward with the Token Ring network scheme and produced an emulator of Sytek's NetBIOS API to allow NetBIOS aware applications from the PC Network era to work over IBM's new Token Ring hardware. This IBM emulator, named NetBIOS Extended User Interface (NetBEUI), expanded the base NetBIOS API created by Sytek with, among other things, the ability to deal with the greater node capacity of Token Ring. A new networking protocol, NBF, was simultaneously produced by IBM to allow its NetBEUI API (their enhanced NetBIOS API) to provide its services over Token Ring – specifically, at the IEEE 802.2 Logical Link Control layer. In 1985, Microsoft created its own implementation of the NetBIOS API for its MS Net networking technology. As in the case of IBM's Token Ring, the services of Microsoft's NetBIOS implementation were provided over the IEEE 802.2 Logical Link Control layer by the NBF protocol. In 1986, Novell released Advanced Novell NetWare 2.0 featuring the company's own emulation of the NetBIOS API. Its services were encapsulated within NetWare's IPX/SPX protocol using the NetBIOS over IPX/SPX (NBX) protocol. In 1987, a method of encapsulating NetBIOS in TCP and UDP packets, NetBIOS over TCP/IP (NBT), was published. It was described in RFC 1001 ("Protocol Standard for a NetBIOS Service on a TCP/UDP Transport: Concepts and Methods") and RFC 1002 ("Protocol Standard for a NetBIOS Service on a TCP/UDP Transport: Detailed Specifications"). The NBT protocol was developed in order to "allow an implementation [of NetBIOS applications] to be built on virtually any type of system where the TCP/IP protocol suite is available," and to "allow NetBIOS interoperation in the Internet." After the PS/2 computer hit the market in 1987, IBM released the PC LAN Support Program, which included a driver offering the NetBIOS API. There is some confusion between the names NetBIOS and NetBEUI. NetBEUI originated strictly as the moniker for IBM's enhanced 1985 NetBIOS emulator for Token Ring. The name NetBEUI should have died there, considering that at the time, the NetBIOS implementations by other companies were known simply as NetBIOS regardless of whether they incorporated the API extensions found in Token Ring's emulator. For MS Net, however, Microsoft elected to name its implementation of the NBF protocol "NetBEUI" – naming its implementation of the transport protocol after IBM's enhanced version of the API. Consequently Microsoft file and printer sharing over Ethernet often continues to be called NetBEUI, with the name NetBIOS commonly used only in reference to file and printer sharing over TCP/IP. More accurately, the former is NetBIOS Frames (NBF), and the latter is NetBIOS over TCP/IP (NBT). Since its original publication in a technical reference book from IBM, the NetBIOS API specification has become a de facto standard in the industry despite originally supporting a maximum of only 80 PCs in a LAN. This limitation was generally overcome industry wide through the transition from NBF to NBT, under which, for example, Microsoft was able to switch to Domain Name System (DNS) for resolution of NetBIOS hostnames, having formerly used the LAN segment compartmentalized NBF protocol itself to resolve such names in Windows client server networks.

When NetBIOS is run in conjunction with Internet protocols (e. g., NBT), each computer may have multiple names: one or more NetBIOS name service names and one or more Internet host names.

The NetBIOS name is 16 ASCII characters, however Microsoft limits the host name to 15 characters and reserves the 16th character as a NetBIOS Suffix.