The NetBIOS over TCP/IP component supports NetBIOS services in a TCP/IP environment. NetBIOS defines a software interface and a naming convention, not a protocol. NetBIOS over TCP/IP is specified by Request For Comment (RFC) 1001 and RFC 1002. NetBIOS over TCP/IP provides the NetBIOS programming interface over the TCP/IP, extending the reach of NetBIOS client and server programs to the Internet Protocol (IP) networks and providing interoperability with various other operating systems.

The Netbt.sys driver is a kernel-mode component that supports the Transmit Diversion Inertie (TDI) interface. Network clients and servers use the TDI interface directly, while traditional NetBIOS applications have their calls mapped to TDI calls through the Netbios.sys driver. Using TDI to make calls to NetBT is a more difficult programming task, but can provide higher performance and flexibility.

The Microsoft Windows NT Workstation service, server service, browser, messenger, and NetLogon services all function as NetBT clients and use TDI to communicate with NetBT. Windows NT also includes a NetBIOS emulator, Netbios.sys, which is a separate component. The emulator takes standard NetBIOS requests from NetBIOS applications and translates them to equivalent TDI functions. The NetBIOS application uses the NetBIOS API to communicate with the NetBIOS emulator.


There are no services associated with this component.

Associated Components

No other components interact with this component.


There are no configurable settings for this component.

© 2006 Microsoft Corporation. All rights reserved.