IRC Net Bandwidth (was IRC and Security)

[Chris Torek]

In article <27773:Apr420:02:0691 at kramden.acf.nyu.edu>
brnstnd at kramden.acf.nyu.edu (Dan Bernstein) writes:
>I believe Chris's comments confirm that routers are just that poor.

`Were', not `are'.  (No doubt some are still in place; it takes time
to throw out broken equipment and software that is in production use.)

I have some more recent information.  Old NSS routers took 6 to 8 ms.
of cpu time to forward each packet, due to excessive stupidity in the
device driver code.  (The routing time was too small to measure in
these systems; `Almost all the per-packet cpu time was spent in device
drivers'.  In addition the old routers added store-and-forward delays
at each T1-to-NSS boundary, because the T1 boards had onboard 386s doing
copies in and out of onboard buffers.  [Better than Z8s, I guess. :-) ])

The new CNSS/ENSS T3 routers are better.  My source has no timings yet
but `we had no trouble using the T3 backbone to saturate a 10Mb/s
ethernet from a machine 1000 miles away'---saturate here means get
approximately 1 MB/s (8 Mb/s) actual data transfer, host-to-host.
(One host was a Cray, the other a Sun SparcStation, both running
experimental software.)  In other words, the problems may not be
completely fixed yet, but they have definitely receded a comfortable
distance.
-- 
In-Real-Life: Chris Torek, Lawrence Berkeley Lab CSE/EE (+1 415 486 5427)
Berkeley, CA		Domain:	torek at ee.lbl.gov