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Definition of NetBEUI in Network Encyclopedia.

What is NetBEUI?

NetBEUI stands for NetBIOS Extended User Interface, is a networking protocol developed by IBM and Microsoft in 1985 that is used for workgroup-size local area networks (LANs) with up to 200 stations. NetBEUI is an extension of the NetBIOS protocol.

NetBEUI - NetBIOS Extended User Interface

NetBIOS Extended User Interface was the primary protocol for LAN Manager and Windows for Workgroups. It is a fast and efficient protocol with low overhead that supports both connection-oriented communication (such as communication for mapping drives using the Net Use command and starting services remotely using the Net Start command) and connectionless communication (such as communication for sending datagrams, registering NetBIOS names, and performing NetBIOS name resolution).

NetBEUI is also self-tuning and implements flow control and error detection. It defines a framing mechanism at the transport layer and implements the LLC2 protocol of the 7 layers OSI Model for networking.

NetBEUI Frame

NetBEUI is supported by all Microsoft Windows network operating systems; its implementation on Windows NT is called the NetBEUI Frame (NBF) protocol.

What is NBF (NetBEUI Frame)?

NetBEUI Frame is an enhanced implementation of the NetBEUI protocol that is available on Microsoft Windows NT operating systems. Some of the enhancements and special features of NetBEUI Frame (NBF) include the following:

  • Support for network driver interface specification (NDIS) version 3 for full 32-bit asynchronous transport layer communication using the transport driver interface (TDI) layer as a NetBIOS emulator
  • Support for automatic memory tuning through dynamic memory allocation
  • Support for dial-up clients through the Remote Access Service (RAS)
  • An extension of NetBEUI’s limit of 256 concurrent NetBIOS sessions to more than 1000 sessions

Although NetBEUI is essentially a nonroutable protocol, NBF supports Token Ring Source Routing on IBM Token Ring networks.

NetBEUI relies on broadcast packets

NetBEUI relies more heavily on broadcast packets than do the TCP/IP and NWLink IPX/SPX-Compatible Transport protocols; you should, therefore, use it only on smaller networks sized for workgroups. Because NetBIOS Extended User Interface is a single-part naming scheme, it is a nonroutable protocol and is generally unsuitable for wide area networks (WANs).