Bill, I think that such terms as "Internet", "Intranet" and "Extranet" DO owe their existence to the wide implementation and use of TCP/IP. So - IMHO - you don't have to worry about TCP/IP to "survive" and "compete" (particularly against SPX/IPX and NetBIOS/NetBEUI). ;) TCP/IP DOES RUN on any Intranet, Extranet and Internet, because - by definition - they DO RUN TCP/IP. Regarding OSI, just consider it as a theoretical reference model particularly well-fitted for training purposes (even if it's NOT limited to that), if this can ease your mind. :) P.S.: on the other hand, I don't think TCP/IP needs to be "protected". It only needs a smooth migration to IPv6. -----Original Message----- From: Bill Cunningham [mailto:billcu@citynet.net] (...) I have been criticized for being too particular about things and too "trolling." I only want TCP/IP to be able to survive and compete. In a world of IPX, SPX, OSI, NetBUEI, etc. TCP/IP should be able to run on any Intranet, Extranet, and of course the Internet, with the best of them. (...)