What is NetBIOS/NetBEUI?
NetBIOS is an acronym and that stands for Network Basic Input Output system. It provides service which allows applications on different computers to talk to each other on a LAN(Local Area Network). As NetBIOS just provides Application Programming Interface, it is not a protocol of networking. NetBIOS is just a session layer service. This session layer service is used to broadcast the computer names.
NetBEUI is also an acronym. It stands for NetBIOS Extended Use Interface. It is a new version of NetBIOS. It is based on computer names and not on IP addresses. Hence NetBEUI is not routable, as it does not use IP addressing. For carrying the data in network, NetBEUI transport protocol is used.
It all started in 1983, when a company called Sytec Inc. developed Application Programming Interface (API) called NetBIOS, a software-based communication system, over IBM PC’s Local Area Network(LAN). NetBIOS was based on the set of networking protocols owned by Sytec for communicating over wire. As the PC LAN supported only up to 80 devices in baseband mode, NetBIOS was developed for limited nodes.
Token Ring scheme for networking was developed by IBM in 1985. For a Token Ring networking scheme, NetBIOS emulator was developed to allow the older applications from PC-Network LAN days to work. This NetBIOS emulator was called NetBEUI. NetBEUI had the ability to support larger number of nodes in the Token Ring networking scheme.
Microsoft too developed its NetBEUI implementation for its networking technology called MS-Net in 1985. Both IBM and Microsoft implemented NetBEUI over IEEE-802.2 Logical Link Control Layer(LLC). Novel also developed advanced Novel Netware 2.0 consisting of Novel’s NetBIOS emulator in 1986.
A method for encapsulating NetBIOS in UDP and TCP packets was published in 1987. It was called NetBIOS over TCP/IP. NetBIOS is used in Token Ring and Ethernet Networks and is included as a part of NetBEUI.
NetBEUI is not a routable protocol. Hence, the mapping of NetBIOS names to IP addresses is done in small networks (where routing is not present) using the following methods,
- IP Broadcasting – the data packet associated with NetBIOS computer name is broadcasted when associated address is not present in the local cache. The host having the name of the NetBIOS computer name returns its own address.
- Imhosts file – In these files NetBIOS computer names are matched with corresponding IP address.
- NBNS – NBNS is the acronym for NetBIOS’s Name Server. This is the server that maps IP addresses to NetBIOS names. The nmbd demon provides this service on Linux machines.
NetBEUI is very efficient in the small networks as it has very few overheads. It is usually faster than TCP/IP. Many times TCP/IP works with the internet but doesn’t function properly when sharing the printers or local files. In such cases NetBEUI could be used for File/Printer sharing.
Windows 95/98, Windows ME, Windows 2000 came with NetBEUI pre installed. Before the advancement of home networking technology to use routers, computers were connected using the hubs and with the help of NetBEUI , user could enter a user friendly name into the browser, map the drives on the network. NetBEUI allowed users to view shared folders.