[e2e] QoS vs Bandwidth Overprovisioning

RJ Atkinson rja at inet.org
Sun Apr 29 13:17:24 PDT 2001

At 12:27 25/04/01, Fred Baker wrote:
>At 08:47 AM 4/25/2001 -0600, Vernon Schryver wrote:
>>Has anyone (esp. major carriers) tried the simple, obvious approach of
>>honoring the old-style IP TOS bits?
>we went through quite a bit of effort on that a few years back, and finally pulled them out of OSPF because the least monetary cost route, the highest bandwidth route, the lowest delay route, and the most reliable route were all the same route.

        This was not true for the DDN trans-Pacific network,
which had deployed OSPF with ToS bit support.  That deployment
particularly used the delay metric to help select between
satellite hop and undersea cable.  The main problem that I
saw with that part of OSPF was that cisco flat refused to 
implement that part of the spec (at that time), so if one 
wanted to implement OSPF with ToS routing support, 
one had to eliminate a major competitor from the bidding 
process.  Sigh.

        I do believe that in many networks, all three paths
would be the same, btw.

rja at inet.org

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