NetBIOS over TCP traditionally with the following ports:
Windows 2000 is a different animal if using the new features and not older NT 4.0 features. Direct hosted "NetBIOS-less" SMB traffic uses port 445 (TCP and UDP). In this situation, a four-byte header precedes the SMB traffic. The first byte of this header is always 0x00, and the next three bytes are the length of the remaining data.Finally, I think the answer is found in if you are using NetBIOS over TCP (ports 137, 138 and 139) or the newer NetBIOS-less SMB traffic over port 445 (TCP & UDP). Fair warning any of the following will not work with a Win 2000 server unless running the following in legacy mode:
IBM OS/2 1.3
Lan Manager 2.2
Microsoft Net Server 1.11
Hewlett-Packard Unix Lan Manager X
This is obvious. Microsoft no longer will support them.
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Ask the Expert: What is NetBIOS?
Ask the Expert: Determining which TCP/IP services are needed
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This was first published in December 2002