Robert Elz writes:
> From: Michael Thomas <[EMAIL PROTECTED]>
>
> | Er, the flow key is src/dst/flowlabel, right? That means it's
> | 64k per host pair which seems like plenty.
>
> Sure, as far as identifying the flow is concerned. I guess I was thinking
> more of a usage model .. that is, src/dst/flowlabel is 272 bits (16 bit
> label), that's a hell of a huge database lookup key - to actually be used,
> (as a hash table lookup key for example) it needs to be reduced to some
> reasonable size.
Considering that the normal 5 tuple is 288 bits,
I think the size of the flow key is already factored
in with the rest of the protocol. Admittedly this
causes a lot of hardware designers waking apnea,
but having another wide key to deal with isn't
nearly as bad as having to deal with the first.
> Doing that the "normal way" (value modulo some prime) seems like it would be
> a much too expensive operation to contemplate. Doing it by calculating some
> kind of CRC of the 272 bits, then using however many bits of that would be
> better, but still not blindingly cheap.
Associative memory is your friend :-)
Mike
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