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Re: looking for SLA examples

  • From: Alex Bligh
  • Date: Sun Sep 23 18:58:01 2001



--On Sunday, 23 September, 2001 3:15 PM -0500 Tim Peiffer <[email protected]> wrote:

some amount for router serialization and queuing delays
(~5 msec/hop?)

5ms per hop? Assuming >=OC-12 backbone, that's way
excessive. At OC-12, a 1500 byte packet takes
20 microseconds to serialize. OK you will statistically
encounter a few queuing delays even on a near-idle
backbone (think about number of other
ingress interfaces), but again these should
be a few packets when the circuit is not
loaded. So 0.5ms per hop seems generous.

Remember that with cloak-of-indeterminacy technologies
such as ATM and MPLS, you may not be able to see many
of the hops.

--
Alex Bligh
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