| SprintLink, Sean Doran <smd@sprint.net> | Sprintlink's T1 backbone is melting down. They're converting to DS- | 3s or parallel T1s in the next few weeks.[see diagram]. T3 customers | feed directly into BB routers to avoid saturating local FDDI rings | For trans-US international connectivity, ICM has 2 T3 between | Stockton, CA and DC. The design goal in separation of SprintLink and | ICM was the assurance of symmetry of routing. | [Context?] preservation of next hop in routing is critical feature | (could not wait for IDRP) | Q: What about fears of an ASpath explosion in routing tables? Sean: | Too late. Already here! Now, admittedly, I haven't gotten slides to you yet (sorry, sorry, firefighting...), but this is a very strange summary. I'm wondering if my accent threw you or something. Our T1 backbone was long gone and dead when I spoke. The last remaining backbone T1s (at that point 3xT1 in parallel between D.C. and Pennsauken and Pennsauken and Chicago) were to be replaced by T3s that week (and they were). The current engineering plan is to build some bandwidth for ICM traffic between D.C. and Stockton, however it won't be T3 and certainly not 2xT3. My slide (again, sorry for not getting you the copy you had asked for; the full colour hand-drawn slides are now in Sweden) showed 10Mbps. There were lots of other things that got elided from the summary, alas, like the fact that THENET and NYSERNET, OARNET and others had started preferring SprintLink over the NSFNET backbone service already, that we had more than 600 operational lines and were providing access in more than 50 countries as of the IETF conference, and the general technical rationale behind "Standard U.S. T3 Backbone Design Number One-B", including the lengthy talk by Peter Lothberg about why we have satellite customer-access ASes rather than one AS for our entire routing domain, and quite alot of discussion about routing symmetry. Fortunately, I tend to keep repeating myself at various conferences, so if I was really that difficult to follow, you can beat me over the head at the Feb. 7-9 NANOG. I have some ASCII pictures here and there I could forward you and anyone else who's interested and who didn't see them on whatever newsfroup I posted them to (ba.internet or alt.internet.services, I can't remember) not long before IETF. Sean.