The MPLS WG Archive

[Curtis Villamizar <curtis@workhorse.fictitious.org>]

In message <5.0.0.25.2.20000928083919.02f81ae0@flipper>, Fred Baker writes:
> At 03:00 PM 9/26/00 -0400, Martin Picard wrote:
> >   Service Providers tend to say that their backbone will never be
> >   congested and if it ever gets there, then, bandwidth will be increased
> >   and therefore no Congestion Management or Congestion Avoidance
> >   mechanisms are necessary.

Thats clearly what the ISP marketing people have to say.

The engineers have to deal with reality and some still assert that
timely delivery of bandwidth is not reality and an infinite budgest
doesn't make good business sense.  The engineers therefore have to
design for the possibility (which some still assert is inevitable)
that congestion will occur at times in various parts of the network.
If increase in access speeds outpace core deployment that includes in
the core.

The network also needs to degrade gracefully when massive outage
occurs.  A few examples in the past 5 or so years (from memory)
include earthquake in southern CA, CO fire in the Bay area, gas leak
(power everything down) in LA area, floods in the mid-west, Amtrak
wreck affecting both sides of track on East, gas company tearing up
wrong pipe (major fiber conduit), and a hurricanes in the East
affecting riverbed fiber, numerous smaller hurricane outages.  I'm not
in operations so this is just a very small subset covering only very
big outages.  The network can't just work well on sunny days.
Congestion avoidance is needed.

Curtis