NetBIOS Frames
NetBIOS Frames (NBF) is a non-
The NBF protocol is broadly, but incorrectly, referred to as NetBEUI. This originates from the confusion with NetBIOS Extended User Interface, an
Overview
NBF protocol uses
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. The lack of support for routable networks means that NBF is only well-suited for small to medium-sized networks, where it has such an advantage over TCP/IP that requires little configuration. 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.[2]
Services
NetBIOS/NetBEUI provides three distinct services:
- Name service for name registration and resolution
- Datagram distribution service for connectionless communication
- Session service for connection-oriented 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 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.
Datagram distribution service
Datagram mode is "
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
Sessions are closed by sending a "Session End" request.
Availability
NBF protocol – apart from DOS, OS/2 and Unix implementations – was officially supported by Microsoft on almost every version of Windows up to Windows 2000,[3] but its use has decreased quickly since the development of NBT.
Microsoft officially dropped support starting with Windows XP,[4] but it is included on the Windows XP CD-ROM and can be installed manually.[5] Windows Vista does not include NetBEUI (means NBF) support at all, but the Windows XP NetBEUI support drivers can be used.[6]
References
- ^ "NetBios NetBEUI NBF Networking Introduction". Archived from the original on 2007-02-07. Retrieved 2007-07-03.
- ^ "NetBios NetBEUI NBF Networking Encapsulation". Archived from the original on 2006-09-15. Retrieved 2006-11-24.
- ^ "NetBEUI support on Windows 2000". Microsoft. Retrieved 2007-03-19.
- ^ "The NetBEUI Protocol Is Not Available in Windows XP (KB306059)". Archived from the original on 20 February 2010. Retrieved 2007-03-19.
- ^ "How to install NetBEUI on Windows XP (KB301041)". Archived from the original on 17 August 2010. Retrieved 2007-03-19.
- ^ "NetBeui on XP and Vista". Archived from the original on 7 March 2016.
External links
- LAN Technical Reference: 802.2 and NetBIOS APIs – includes NBF protocol specifications
- Comparison of Windows NT Network Protocols