Re: [irs-discuss] About ALTO Vs. BGP-LS (Noel Chiappa) Tue, 07 August 2012 15:15 UTC

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Date: Tue, 7 Aug 2012 11:15:29 -0400 (EDT)
From: (Noel Chiappa)
Subject: Re: [irs-discuss] About ALTO Vs. BGP-LS
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    > From: "Y. Richard Yang" <>;

    > Glad that you also like the idea of different levels of details of the
    > network topology. If the ALTO Server is given a detailed topology
    > ... we can offer multiple topology operators/aggregators to explore the
    > detailed topology, according to need and policy.

Too bad we have a routing architecture that deals (as its fundamental
currency) in destination tables, rather than topology - and, in particular,
in a multi-level representation of the toplogy. Then all this stuff would
just fall out naturally.

(And if I sound somewhat cranky, perhaps people will forgive me - although I
expect not that many on this list will know what I'm implicitly referring to.)

    > There are studies on representation of multi-level graphs that we can
    > try to take advantage of. This can be a subject for the group to explore.

There's a PhD thesis which is relevant to this area (since part of it is
about clustering, i.e. in representing an area of the graph without full
detail, one has to decide where to set the boundaries of said part):

  Jacob Hagouel, "Issues in Routing for Large and Dynamic Netoworks",
  Columbia University, 1983

A lot of it is irrelevant (to me, at least), since it's talking about
distributed path computation (which I have long since concluded is 'buggy
whip' technology), but the clustering, etc, content is good.