Bill, >> Michel Py wrote: >> The bottom line is: lots of people are going to continue >> using the OSI model. We don't need two different models. > Fine let them use OSI or whatever they choose. But if TCP/IP has > incompatibilies with token-ring LANS, this should probably be > worked on. I believe in freedom to choose whatever model you wish, > but TCP/IP is the Internet's model. Why does TCP/IP have trouble > passing a token ring around hosts? I've never really got into that > issue. I thought TCP/IP worked fine in Intranets. It's not a matter of compatibility, it's a matter of semantics. The point is *not* if TCP/IP works fine in Intranets; it does and it is becoming the only protocol suite on Intranets as well (faster in my dreams than in reality). The point I am trying (with difficulties ;-) to make here is: The OSI model as of today is a conceptual model. In the past, some good stuff came out of it and some real junk too; that was in the past. Today, if your protocol maps nicely to it, fine. If it does not, though. That being said, the Internet is not the only network out there and even on the Internet itself there are parts where the 4 1/2 layers TCP/IP model is way too simple. Take a reality check: go to Border's or any bookstore and browse books about networking or internetworking. Tell me if you find the TCP/IP model there or the OSI model. As I said before, the time to design according to a model is way passed. What I do today as a protocol designer is based on my and other people's experience, not on a model that was invented 20 years ago before nobody could really envision today's Internet. In other words: I am not preaching for the ISO or any other model being a set of design guidelines. What I am trying to say is that when defining terms (read the subject of this thread) the OSI model is more precise than the TCP/IP one and is still the one used by people including myself that have a broader horizon than TCP/IP or the Internet. Michel.