> > Unnh, UDP stands for User Datagram Protocol. > > But it is not particularly confusing. > > Bob Braden User Datagram protocol is pretty self explanatory as far as datagrams go. But there's so many protocols out there now some like PPTP that are proprietary. I've read several books on TCP/IP and they can be contradictory and more confusing than RFCs. If data is to pass from one level to another and that's not true in all cases, then there should be a new term for the data 'packet' at the new level. When someone says to me 'datagram.' I don't know what level of TCP/IP they're talking about. It could be IP datagrams at Internet layer, or UDP datagrams at Transport layer. Datagram only defines a connectionless protocol according to rfc 1122. I hope that clears up any misunderstanding. I don't want to take away the definition "connectionless protocol" only somehow communicate to another what layer I'm talking about. This can be done by saying UDP or IP datagram if one knows these protocols are at Transport and Internet levels. But these are well known protocols also. Some RFCs are vague enough and short enough to say datagram and not mention a layer nowdays. Now if someone says to me 'frame.' I think PPP first off, not necessarily Network layer, if that's where it is, rfc 1661 looks like it was written in accordance with the OSI model. I'm not sure of that one. As far as being confusing, maybe the most confusing part is that we have TCP/IP and OSI. I claim to know nothing of OSI. Maybe common terms between these two and other models based on info -packets and not layers would be a way to go. Trying to fit 7 layers into 4 layers is a topic of networking books everywhere. Maybe you and the others Bob can help clear my head and focus on a common terminology, perhaps between different models such as OSI and TCP/IP so that a datagram comes from one layer of perhaps each of these models. TCP/IP and OSI. --Bill >