Internet testing

Curtis Villamizar curtis at
Wed Nov 2 07:03:09 UTC 1994

In message <9411012050.AA07250 at>, "Matt Mathis" writes:
> We are ready to perform end-to-end performance testing across the new NSF
> architecture.  PSC has a whole battery of TCP and IP diagnostics available
> from a test network, which can be exercised without exposing any production
> users to untested infrastructure.


Any testing must be well defined and brief, conducted off hours and
announced in advance, since this is the Internet you're going to be
pounding, not a test network.  Please coordinate with the ANS NOC.  If
we send NSR messages and anyone objects, we may have to cancel or
reschedule tests.  This could get tedious.

ANS has an SGI Indy/SC in Maui at MHPCC that is there for testing
purposes.  Perhaps we can go off line and contact the folks at MHPCC
and see if they would mind if we did some testing to establish a
baseline.  The delay (excluding queueing delay) between your ENSS and
MHPCC is 117 msec.  The congestion point will almost certainly be
Cleveland or Chicago (both have our latest code - no RED).  I'm not
sure what the typical loads are in the middle of the night, but if I
remember correctly it's under 5 mB/s at that time.  Perhaps SDSC would
like to participate.  SDSC is 70 msec from PSC.

fyi - PSC is 60 msec from Hayward (approximately the PacBell NAP),
MHPCC is 61 msec away, and SDSC 14 msec away.  The Sprint NAP is 136
msec from MHPCC, 89 msec from SDSC and 27 msec from PSC.

I'm not sure how you are going to test the NAPs.  Two party tests
can't put a bottleneck at the NAP if ingress equals egress.  The
interesting tests must involve at least a small amount of traffic from
a third party.  (On ANSNET we probably have 100 or more third parties
contributing their traffic to your tests - and maybe wondering why the
Mosaic globe suddenly started spinning real slow).  We may need a
volunteer on MCINET and one on SprintLink (at least one with DS3
access? - that narrows the list, doesn't it).  I think MCI and maybe
Sprint has hosts at the PacBell NAP.  That would work with both
sending to you.

> The network psc-hs-test (192.88.115), containing only the host
> ( is being announced to ANSnet (AS690), and
> from ANSnet to all peers at the NAPs.  It is not announced by ANSnet to any
> other interconnects or providers.  We encourage all providers to accept this
> route via the NAPs as soon as possible.
> If an RSP announces a test network to their new NSP, and also has the route
> announced across the NAPs, we can establish end-to-end connectivity through
> the new infrastructure.  We are in a position to exercise such a path at load
> s
> beyond those attainable by most users.   

We know.  :-)

> Depending on the target host available at the RSP, we can run large window
> TCP, mping or Jamshid's instrumented traceroute.
> We do need to be careful about maximum load because some of the segments are
> carrying production traffic.  Since TCP "does the right thing" in the presenc
> e
> of congestion, TCP tests can be run at what ever bandwidth the network will
> support.  We will limit IP performance tests to avoid sustained or high packe
> t
> loss.

An understatement: "We do need to be careful ...".

> [ ... ]
> There is an issue of acceptance criteria: We are not parties to the
> provider contracts, and are not in a position to tell providers what they
> should deliver to their customers.  Furthermore, it is known that much of the
> technology is being pushed into service faster than comfortable.  None the
> less, we believe that there are some minimal requirements that should be
> met in all parts of the R&E Internet, if not the entire Internet.
> Required on day one (Note the vague words):
> 	- Mostly not congested.
> 	- Low loss when not congested.
> 	- Sufficient queuing to smooth some of the inherent burstyness.
> 	- Sane congested behavior at likely choke points.  Sane means that
> 	  actual IP throughput should be constant or at worst fall gently
> 	  with load rising beyond the onset of congestion.

Well stated.

Other than to point out that we must be considerate of people actually
trying to use this small part of the Internet thingie (ANSNET), I
think you proposal to perform some testing as early as possible is a
good idea.  I would have preferred if this sort of testing happenned
in a lab or on a test network under realistic conditions first.  Part
of our testnet is now down, scavenged to fix a problem at a production
POP (last resort supply of spares until people start to turn in their
ENSSs) so our testing is temporarily down.  I think we should at least
give the NAP operators the opportunity to state what further testing
they plan to do, before testing on their behalf on the real network.


PS - over and out - or off-line to be more accurate.

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