Yes, it might. I like your suggestion, but need some feedback from Ian
on it.

On Thu, Apr 13, 2006 at 01:59:02PM +0100, Michael Rogers wrote:
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> Matthew Toseland wrote:
> > Yep. One request send rate for all neighbours combined.
> ...
> > If it's local, it backs off. Either way it reduces its overall send
> > rate via AIMD.
> 
> This seems like it might lead to a chain reaction: when a request is
> rejected, all nodes along the path reduce their rate for all neighbours,
> causing queues to fill up and additional requests to be rejected. For
> example:
> 
>     E
>     |
> A---B---C---D
>     |
>     F
> 
> A sends a request along the path ABCD. D rejects the request because
> it's overloaded, so B and C reduce their rates. E's request along the
> path EBF gets rejected because B has reduced its rate, even though none
> of the nodes along EBF is overloaded.
> 
> Here's what I'd suggest instead:
> 
> * Keep a separate rate for requests to each neighbour
> * Decrease the rate when a _local_ RejectedOverload is received
> * Send a RejectedOverload if the queue is full
> 
> In the example above, only C's rate to D would be reduced initially, but
> if A continued to send requests at a high rate then C's queue to D would
> fill up and it would send a RejectedOverload to B, which would reduce
> its rate to C, and so on until A's traffic was quenched. The traffic
> along EBF would be unaffected.
> 
> Backoff seems to be redundant under this scheme...
> 
> Cheers,
> Michael
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-- 
Matthew J Toseland - toad at amphibian.dyndns.org
Freenet Project Official Codemonkey - http://freenetproject.org/
ICTHUS - Nothing is impossible. Our Boss says so.
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