NetBEUI
Encyclopedia
NetBIOS Frames or NBF protocol is a non-routable network- and transport-level data protocol
most commonly used as one of the layers of Microsoft Windows
networking in the 1990s. NBF protocol or NetBIOS
over IEEE 802.2
LLC
is used by a number of network operating systems released in the 1990s, such as LAN Manager
, LAN Server
, Windows for Workgroups, Windows 95
and Windows NT
. Other protocols, such as NBT (NetBIOS over TCP/IP), and NetBIOS-over-IPX/SPX
also implement the NetBIOS/NetBEUI services over other protocol suites.
NBF protocol is commonly confused with NetBEUI (NetBIOS Extended User Interface; an extension to the NetBIOS API that was originally developed in conjunction with NBF protocol; the two of them developed to allow NetBIOS programs to run over IBM
's new token ring network). Microsoft
promulgated this confusion by labelling its NBF protocol implementation NetBEUI. NBF is a protocol and NetBEUI an application programming interface
extension.
service, and 802.2 type 2 mode to provide the NetBIOS/NetBEUI session service (virtual circuit
). NBF protocol makes wide use of broadcast messages, which accounts for its reputation as a chatty interface.
Sytek
developed NetBIOS for IBM for the PC-Network
program and was used by Microsoft for MS-NET in 1985. In 1987, Microsoft and Novell
utilized it for their network operating systems LAN Manager and NetWare.
Because NBF protocol is unroutable it can only be used to communicate with devices in the same broadcast domain
, but being bridgeable it can also be used to communicate with network segments connected to each other via bridges. This means that it is only well-suited for small to medium-sized networks
; the NetBIOS/NetBEUI services must be implemented atop other protocols, such as IPX and TCP/IP (see above) in order to be of use in an internetwork.
NBF protocol implements all of these services.
In addition, to start a session or to send a datagram to a particular host rather than to broadcast the datagram, NBF protocol has to determine the MAC address
of the host with a given NetBIOS/NetBEUI name; this is done by sending a "Name Query" packet, the response to which will have the MAC address of the host sending the response, i.e. the host with that name.
Sessions are established by exchanging packets. The computer establishing the session sends a "Name Query" request, specifying that a session should be initialized. The computer with which the session is to be established will respond with a "Name Recognized" response indicating either that no session can be established (either because that computer is not listening for sessions being established to that name or because no resources are available to establish a session to that name) or that a session can be established (in which case the response will include a local session number to be used in subsequent packets). The computer that is starting the session will then send a "Session Initialize" request which will prompt a "Session Confirm" response.
Data is transmitted during an established session by data packets. IEEE 802.2 handles flow control and retransmission of data packets. Because NetBIOS/NetBEUI allows packets to be sent that are larger than the largest packet that could be transmitted on a particular MAC
layer, a NetBIOS/NetBEUI packet might have to be transmitted as a sequence of "Data First Middle" packets and a "Data Only Last" packet; packets that do not need to be segmented in that fashion will be sent as a single "Data Only Last" packet. An acknowledgment will be sent for all "Data Only Last" packets that are successfully received; this will also acknowledge all preceding "Data First Middle" packets.
Sessions are closed by sending a "Session End" request.
, but its use has decreased quickly since the development of NBT.
Microsoft officially dropped support starting with Windows XP
, but it is included on the Windows XP CD-ROM and can be installed manually. Windows Vista does not include NetBEUI support at all, but the Windows XP NetBEUI support drivers can be used.
Communications protocol
A communications protocol is a system of digital message formats and rules for exchanging those messages in or between computing systems and in telecommunications...
most commonly used as one of the layers of Microsoft Windows
Microsoft Windows
Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
networking in the 1990s. NBF protocol or NetBIOS
NetBIOS
NetBIOS 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...
over IEEE 802.2
IEEE 802.2
IEEE 802.2 is the IEEE 802 standard defining Logical Link Control , which is the upper portion of the data link layer of the OSI Model. The LLC sublayer presents a uniform interface to the user of the data link service, usually the network layer...
LLC
Logical Link Control
The logical link control data communication protocol layer is the upper sub-layer of the data link layer in the seven-layer OSI reference model...
is used by a number of network operating systems released in the 1990s, such as LAN Manager
LAN Manager
LAN Manager was a Network Operating System available from multiple vendors and developed by Microsoft in cooperation with 3Com Corporation. It was designed to succeed 3Com's 3+Share network server software which ran atop a heavily modified version of MS-DOS.-Development history:LAN Manager was...
, LAN Server
LAN Server
IBM LAN Server started as a close cousin of Microsoft LAN Manager and first shipped in early 1988. It was originally designed to run on top of Operating System/2 Extended Edition. The network client was called IBM LAN Requester and was included with OS/2 EE 1.1 by default. IBM LAN Server started as...
, Windows for Workgroups, Windows 95
Windows 95
Windows 95 is a consumer-oriented graphical user interface-based operating system. It was released on August 24, 1995 by Microsoft, and was a significant progression from the company's previous Windows products...
and Windows NT
Windows NT
Windows NT is a family of operating systems produced by Microsoft, the first version of which was released in July 1993. It was a powerful high-level-language-based, processor-independent, multiprocessing, multiuser operating system with features comparable to Unix. It was intended to complement...
. Other protocols, such as NBT (NetBIOS over TCP/IP), and NetBIOS-over-IPX/SPX
IPX/SPX
IPX/SPX stands for Internetwork Packet Exchange/Sequenced Packet Exchange. IPX and SPX are networking protocols used primarily on networks using the Novell NetWare operating systems.-Protocol Layers:...
also implement the NetBIOS/NetBEUI services over other protocol suites.
NBF protocol is commonly confused with NetBEUI (NetBIOS Extended User Interface; an extension to the NetBIOS API that was originally developed in conjunction with NBF protocol; the two of them developed to allow NetBIOS programs to run over IBM
IBM
International Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
's new token ring network). Microsoft
Microsoft
Microsoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...
promulgated this confusion by labelling its NBF protocol implementation NetBEUI. NBF is a protocol and NetBEUI an application programming interface
Application programming interface
An application programming interface is a source code based specification intended to be used as an interface by software components to communicate with each other...
extension.
Overview
NBF protocol uses 802.2 type 1 mode to provide the NetBIOS/NetBEUI name service and datagramDatagram
A datagram is a basic transfer unit associated with a packet-switched network in which the delivery, arrival time, and order are not guaranteed....
service, and 802.2 type 2 mode to provide the NetBIOS/NetBEUI session service (virtual circuit
Virtual circuit
In telecommunications and computer networks, a virtual circuit , synonymous with virtual connection and virtual channel, is a connection oriented communication service that is delivered by means of packet mode communication...
). NBF protocol makes wide use of broadcast messages, which accounts for its reputation as a chatty interface.
Sytek
Sytek Inc
The Sytek Inc., now known as , created the NetBIOS protocol, used by Microsoft to make its networks with MS Windows 3.x and 9x.Sytek was founded in Silicon Valley and last officed in their own building on Charleston Road in Mountain View. During this crucial period in LAN development, there were...
developed NetBIOS for IBM for the PC-Network
PC-Network
PC-Network was a LAN system consisting of network cards, cables, and a small device driver known as NetBIOS . It used a data rate of 2 Mbit/s....
program and was used by Microsoft for MS-NET in 1985. In 1987, Microsoft and Novell
Novell
Novell, Inc. is a multinational software and services company. It is a wholly owned subsidiary of The Attachmate Group. It specializes in network operating systems, such as Novell NetWare; systems management solutions, such as Novell ZENworks; and collaboration solutions, such as Novell Groupwise...
utilized it for their network operating systems LAN Manager and NetWare.
Because NBF protocol is unroutable it can only be used to communicate with devices in the same broadcast domain
Broadcast domain
A broadcast domain is a logical division of a computer network, in which all nodes can reach each other by broadcast at the data link layer. A broadcast domain can be within the same LAN segment or it can be bridged to other LAN segments....
, but being bridgeable it can also be used to communicate with network segments connected to each other via bridges. This means that it is only well-suited for small to medium-sized networks
Computer network
A computer network, often simply referred to as a network, is a collection of hardware components and computers interconnected by communication channels that allow sharing of resources and information....
; the NetBIOS/NetBEUI services must be implemented atop other protocols, such as IPX and TCP/IP (see above) in order to be of use in an internetwork.
Services
NetBIOS/NetBEUI provides three distinct services:- Name service for name registration and resolution
- Session service for connection-oriented communication
- DatagramDatagramA datagram is a basic transfer unit associated with a packet-switched network in which the delivery, arrival time, and order are not guaranteed....
distribution service for connectionless communication
NBF protocol implements all of these services.
Name service
In order to start sessions or distribute datagrams, an application must register its NetBIOS/NetBEUI name using the name service. To do so, an "Add Name Query" or "Add Group Name Query" packet is broadcast on the network. If the NetBIOS/NetBEUI name is already in use, the name service, running on the host that owns the name, broadcasts a "Node Conflict" message on the network.In addition, to start a session or to send a datagram to a particular host rather than to broadcast the datagram, NBF protocol has to determine the MAC address
MAC address
A Media Access Control address is a unique identifier assigned to network interfaces for communications on the physical network segment. MAC addresses are used for numerous network technologies and most IEEE 802 network technologies, including Ethernet...
of the host with a given NetBIOS/NetBEUI name; this is done by sending a "Name Query" packet, the response to which will have the MAC address of the host sending the response, i.e. the host with that name.
Session service
Session mode lets two computers establish a connection for a "conversation," allows larger messages to be handled, and provides error detection and recovery.Sessions are established by exchanging packets. The computer establishing the session sends a "Name Query" request, specifying that a session should be initialized. The computer with which the session is to be established will respond with a "Name Recognized" response indicating either that no session can be established (either because that computer is not listening for sessions being established to that name or because no resources are available to establish a session to that name) or that a session can be established (in which case the response will include a local session number to be used in subsequent packets). The computer that is starting the session will then send a "Session Initialize" request which will prompt a "Session Confirm" response.
Data is transmitted during an established session by data packets. IEEE 802.2 handles flow control and retransmission of data packets. Because NetBIOS/NetBEUI allows packets to be sent that are larger than the largest packet that could be transmitted on a particular MAC
Media Access Control
The media access control data communication protocol sub-layer, also known as the medium access control, is a sublayer of the data link layer specified in the seven-layer OSI model , and in the four-layer TCP/IP model...
layer, a NetBIOS/NetBEUI packet might have to be transmitted as a sequence of "Data First Middle" packets and a "Data Only Last" packet; packets that do not need to be segmented in that fashion will be sent as a single "Data Only Last" packet. An acknowledgment will be sent for all "Data Only Last" packets that are successfully received; this will also acknowledge all preceding "Data First Middle" packets.
Sessions are closed by sending a "Session End" request.
Datagram distribution service
Datagram mode is "connectionless". A datagram is sent with a "Datagram" packet if it is being sent to a particular NetBIOS/NetBEUI name, or a "Datagram Broadcast" packet if it is being sent to all NetBIOS/NetBEUI names on the network.Availability
NBF protocol - apart from DOS and Unix implementations - is officially supported by Microsoft on almost every version of Windows up to Windows 2000Windows 2000
Windows 2000 is a line of operating systems produced by Microsoft for use on personal computers, business desktops, laptops, and servers. Windows 2000 was released to manufacturing on 15 December 1999 and launched to retail on 17 February 2000. It is the successor to Windows NT 4.0, and is the...
, but its use has decreased quickly since the development of NBT.
Microsoft officially dropped support starting with Windows XP
Windows XP
Windows XP is an operating system produced by Microsoft for use on personal computers, including home and business desktops, laptops and media centers. First released to computer manufacturers on August 24, 2001, it is the second most popular version of Windows, based on installed user base...
, but it is included on the Windows XP CD-ROM and can be installed manually. Windows Vista does not include NetBEUI support at all, but the Windows XP NetBEUI support drivers can be used.
External links
- LAN Technical Reference: 802.2 and NetBIOS APIs - includes NBF protocol specifications
- About NetBEUI
- Comparison of Windows NT Network Protocols