how many bits of entropy do we need for load balancing?

Masataka Ohta mohta at
Tue Dec 15 14:43:58 UTC 2020

Sorry to have sent unedited mail.

On 2020/12/15 3:16, Lawrence Wobker wrote:

> So I’d argue that the pedantic answer is “you need only as many bits
> of entropy as your largest fan out” — meaning that 10 bits would
> allow 1024-way ECMP.  But I don’t think that’s what you were actually
> after...

But, that is the proper answer for backbones where fair load
balancing is really required with many flows from many sources
and destinations.

As the required number of bits for the entropy is, as you pointed
out, very small, at the backbones, even entropy by source and
destination addresses should be, in practice, enough.

						Masataka Ohta

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