Subject: Re: Duration

From: David Newman <[email-masked]>
Date: Fri, 18 Jun 1999 10:46:32 -0400

> Sorry, David - I just don't think 1 second is long enough to get good,
> repeatable and reliable measurements.  

Um, my 1-second suggestion was made in jest.

We are getting too hung up on numbers here. A test duration of 30
seconds (or 10 or 60, take your pick) is not meaningful in the context
of gigabit devices since they can't buffer anywhere near that much
traffic (and neither can any analyzer, should packet capture be
required). 

> We've seen in the field a number of
> devices that appear to behave very nicely for durations of 10 seconds;

I've seen similar fluctuations when traffic is monitored for 4 hours
rather than 1 hour, or for 24 hours instead of 4 hours. I take your
point that this is only a SHOULD and not a MUST, but still if a number
is given it should mean something. I'm OK with a 30-second duration
(it's what I use too, at least for 10- and 100-Mbit/s Ethernet), but
that's still probably way longer than is necessary for measuring
steady-state forward rates of gigabit or faster devices, given current
memory specs.

dn