too many routes

Sean M. Doran smd at
Thu Sep 11 01:03:20 UTC 1997

Vadim Antonov <avg at> writes:

> Sprint never used cisco 4000s in the backbone.  Just FYI.

True.  The only one I ever remember was the DANTE access
router which was dropped in place before AS-path
prepending in software came about, and that wasn't a
backbone router by any stretch of the imagination.

There may have been one deployed to handle NACSIS or some
other odd case at some point, however I don't remember it

> Historically, memory limitation was because CSC/4 board in AGS/+
> routers had memory soldered in.  The box was absolute top of the line
> when it started to fall over.

Sprint, in fact, was in an OK position since it was
possible to eliminate full routing on most of the AGS+es in
relatively short order once the memory problem became more
apparent.  I believe you and I got to the point where none
of our AGS+es had full routing before people like JANET
started having regular problems and had to start dropping
routes from places like PSI entirely in order to have any
connectivity at all.

The AGS+ -> 7000 migration was a conceptual disaster,
since the RP+SP combination simply didn't perform well
under load.

The SSP made things happier, particularly when things like
selective packet drop were implemented, and this in
essence led to Peter's frequent (and pretty accurate)
complaint that the initial introduction of the 7500
compared to a 7000 + RP + SSP was a step backwards.

(Several people who used to be at cisco, and some who
still are, also have been heard making that complaint from
time to time...)

> Can you spell "economies of scale"?  Or "using fiber at cost means
> owning the fiber"?   If you want to play the backbone game you've
> got to own long-haul transmission facilities.

And if you own such transmission facilities you have to
hope that your competitiveness police don't force you to
separate your transmissions facilities from your
value-added services, and require the transmissions people
to offer consistent pricing to all parties including the
value-added services people.

Of course, if bandwidth becomes much cheaper than you had
bargained for initially, it could be a disadvantage to be
trapped into using your own company's transmissions
facilities with a requirement of a decent ROI, so it kinda
cuts both ways.

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