It's still ATM day, 'cause something else just occurred to me: | Consider the following configuration | | ________ _______________________ ________ | | Router | loop A | | loop C | Router | | | A |=========| Wide-Area ATM Service |========| C | | |________| |_______________________| |________| | | | | local loop B | | | ________ | | Router | | | B | | |________| How is one doing bandwidth allocation in this scheme? Are we assuming CBR (to be very conservative) (or VBR with V=0 for those that don't do CBR)? If so, then local loop B is really two circuits, one of BW X and the other of BW 1-X. Moreover, continuing with the thought of CBR or the equivalent, if one has a hundred routers in one's network, how does one allocate a fixed bandwidth from B to each router? Or does one overcommit and lean on UBR or ABR or some other *BR? These are serious questions I don't have an answer to, and come a result of having remembered the paragraph below and of remembering that a couple of our competitors have very large (admittedly "Frame Relay") PVC meshes. Sean. | The desire for a full mesh of VCs between routers becomes more compelling | if you have more than three routers. The diagram is left as an exercise | to the reader; I rather dislike having to draw in ASCII.