nanog mailing list archives
Re: OSPF multi-level hierarchy: Necessary at all?
From: Sean Donelan <SEAN () SDG DRA COM>
Date: Fri, 28 May 1999 3:01:16 -0500
avg () kotovnik COM (Vadim Antonov) writes:
Well, actually it is not that bad. The biggest number of locations is probably found in AT&T phone network - 250 or so. Sprint is in few dozen. The existing IGPs are quite happy with that kind of complexity, so if you belong to the "one-router-per-POP" school of thought the IGP complexity is a non-issue.
Well, the phone system is already hierarchial. The top-level is pretty small, it is the second and third levels which are monsters. There are about 100,000 NXX's in the country. California has the largest state with about 12,000. The Los Angeles LATA is the biggest at about 5,000. Within PacBell there are about 800 CLLI locations for the Los Angeles LATA, not including all the other CLECs who may have locations in LA. Getting from the relatively few IXC access tandems to those 800 locations is the trick. I may be doing something wrong, but I've found OSPF gets a bit cranky with far less than 800 routers and 5,000 routes in an area. -- Sean Donelan, Data Research Associates, Inc, St. Louis, MO Affiliation given for identification not representation
Current thread:
- Re: OSPF multi-level hierarchy: Necessary at all?, (continued)
- Re: OSPF multi-level hierarchy: Necessary at all? Alex P. Rudnev (May 27)
- Re: OSPF multi-level hierarchy: Necessary at all? Alex Zinin (May 27)
- Re: OSPF multi-level hierarchy: Necessary at all? Alex P. Rudnev (May 27)
- Re: OSPF multi-level hierarchy: Necessary at all? Vadim Antonov (May 27)
- Re: OSPF multi-level hierarchy: Necessary at all? Alex P. Rudnev (May 27)
- RE: OSPF multi-level hierarchy: Necessary at all? Jessica Yu (May 27)
- Re: OSPF multi-level hierarchy: Necessary at all? Vadim Antonov (May 27)
- Re: OSPF multi-level hierarch: side question Steve Meuse (May 28)
- Re: OSPF multi-level hierarch: side question Alex P. Rudnev (May 28)
- Re: OSPF multi-level hierarch: side question Steve Meuse (May 28)
- Re: OSPF multi-level hierarchy: Necessary at all? Vadim Antonov (May 27)
- Re: OSPF multi-level hierarchy: Necessary at all? Sean Donelan (May 28)
- Re: OSPF multi-level hierarchy: Necessary at all? Alex P. Rudnev (May 28)
- Re: OSPF multi-level hierarchy: Necessary at all? Alex Zinin (May 28)
- Re: OSPF multi-level hierarchy: Necessary at all? Alex P. Rudnev (May 28)
- Re: OSPF multi-level hierarchy: Necessary at all? Jessica Yu (May 28)
- Re: OSPF multi-level hierarchy: Necessary at all? Alex P. Rudnev (May 28)
- Re: OSPF multi-level hierarchy: Necessary at all? Jessica Yu (May 28)
- Re: OSPF multi-level hierarchy: Necessary at all? Alex P. Rudnev (May 31)
- Re: OSPF multi-level hierarchy: Necessary at all? Alex P. Rudnev (May 28)