Which RFC?

Bill Woodcock woody at zocalo.net
Thu Jan 2 16:16:27 UTC 1997

        > Anyone know *which* RFC says a packets should be routed using
        > the most specific route in a routing table, not (for instance)
        > the first route in the table that matches, or, for instance,
        > using a less specific route that has a better metric?
    It might be worth your while to look through the sections of RFC 791
    and subsequent revisions which define the second byte of the IP
    header, which sets the delivery-priority and the class-of-service for
    the packet.  The class-of-service (type-of-service?) field lets you
    specify whether you want the shortest, largest, cheapest, or most
    reliable route, those being mutually exclusive.  In my experience,
    both fields are set to 0 on just about all packets, which doesn't
    specify any requested class-of-service.  That presumably leaves the
    router free to choose any route it likes, at its discretion.
        > This is so basic I hardly know where to find it
    If the router, in its discretion, chooses to route the packet in the
    wrong direction, that should be easily demonstrated and reasonably
    incontrovertable, no? What's your vendor's argument in favor of
    shipping the packet to a nearby site which isn't associated with your
    destination?  I'm kind of curious to hear it...
    Who's the vendor?  Please humiliate them publicly.  :-)

bill woodcock woody at zocalo.net woody at nowhere.loopback.edu user at host.domain.com

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