[ih] The story of BGP?

[John Curran]

On Feb 8, 2013, at 12:30 PM, Scott Brim <scott.brim at gmail.com> wrote:

> On Thu, Feb 7, 2013 at 6:20 PM, Louis Mamakos <louie at transsys.com> wrote:
>> Some other random thoughts..
>> 
>> I think one of the drivers for a replacement for EGP was the arrival of the NSFNET, and the need to support a topology that wasn't the mostly-strict hierarchy that was rooted in the single set of core routers on the ARPANET.  The NSFNET backbone along with the various NSF sponsored regional networks as well as other research networks were quite a challenge to glue together, with somewhat ill-defined borders between networks and IGP domains that spanned multiple networks and their administrators.  A better tool was desperately needed.
> 
> One of the most entertaining moments in my history of IETF involvement
> was when Hans-Werner Braun and I explained NSFNet and ARPAnet routing
> interworking.  Everything was still hierarchical so we did it all with
> RIP and a lot of following default routes.  Dave Clark slapped his
> forehead.  Jon Postel just shook his head.  Yes we needed something
> like BGP but that took a few years.

Yes, it was RFC 1092/1093 that nicely documented the problem with strictly hierarchical 
EGP routing when the topology actually wasn't hierarchical... EGP+IGRP combined with the
exceptions for the interesting lateral connections often resulted in breakage for anyone 
at multiple NSFNET NSS connections (e.g. CSNET with NSS 8/JVNC, NSS 6/SDSC) unless some
real care was taken in configs.

/John