I am going to have to call bullshit on the MPLS fast reroute thing
there Wayne. The canonical counterexample is Sprint.
To be sure, Sprint and Ebone have shown that it is possible to
run a very high quality (low jitter) pure IP network, but...
Excellent engineering and ops folks top the list, followed closely
by sufficient capacity,
This poses a bit of a problem. If we accept that these two
things are absolutely necessary in order to run a pure IP
network, i.e. no MPLS and no ATM or frame at layer 2, then
that leaves out most of the world. By definition, excellent
engineering and ops folks are the top minority in their
field. If we assume that 10% of engineering and ops folks
are "excellent", that means that 90% of network operators
are unable to play this game. Also, not everyone has a
facilities-based network where they can afford "sufficient"
And last but not least, this whole discussion was about
diversity and resilience. I would not be happy to see a
network ecosystem in which every network was designed and
run like Sprint's network. There is a place for MPLS and
in the end, it may even prevail because of its ability
to handle multiple best paths and to do fast reroute.
The jury is still out on that.