[Isis-wg] draft-ietf-isis-traffic-01.txt

[Jeff Learman]

Tony,

Right: black holes, not loops.

Never mind,
Roseanna Roseannadanna

At 03:51 PM 10/26/99 -0700, Tony Li wrote:
>
>|  Earlier, I pointed out what I though was a problem with the 24-bit
metrics,
>|  namely, that MAX_PATH_METRIC increased from 1024 to a much larger value.
>|  
>|  If you are running traffic engineering metrics in parallel with existing
>|  TLVs, which value for MAX_PATH_METRIC should be used?  Must all routers
>|  in the subdomain support the new TLVs before they are used at all,
>|  to avoid routing loops that would occur if some paths exceed the smaller
>|  MAX_PATH_METRIC?
>
>
>Would inconsistent MAX_PATH_METRICs lead to forwarding loops?  Or to
>blackholes? 
>
>In any case, if you're going to run with both metrics, then in normal
>operations, the metric would have to be smaller than 1024.  If it were to
>exceed this, presumably due to an outage, then newer systems might find a
>path while older systems didn't.  This would seem like a blackhole.
>
>And of course, if everything is a new system, you have a valid path.
>
>I'm not sure I see the problem.
>
>Tony
>
>
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  Jeff Learman                           Internet:     jjl@one.com
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