There has been a long and ongoing controversy over whether NetBEUI is better in LAN environments than TCP/IP. Most of the reasons for the controversy seem to stem from the fact that NetBEUI is non-routable -- i.e., it's designed to work in a LAN rather than a wide-area network like the Internet and, therefore, has less overhead.
The truth is that the difference in overhead on a well-tuned system is not major enough to justify keeping NetBEUI around. There are also problems that can arise with having both NetBEUI and TCP/IP on the same system, especially if an application mistakenly tries to encapsulate NetNEUI into TCP/IP (which just slows everything down). NetBEUI is also no longer installed by default in Windows systems, and may not be supported any longer in the near future. The best thing to do is just use TCP/IP in a fast network environment -- i.e., use a 100-megabit full duplex switch -- and not use NetBEUI, as it tends to create or preserve more problems than it solves in the long run.
This was first published in December 2002