Ethernet traffic metrics: measuring incremental traffic?

[Matt Landau]

    I need some information on how to measure and compute meaningful metrics
about ethernet performance and traffic levels, in particular about "the
amount of traffic generated" by adding diskless Sun 3's to a local ethernet.

    Let's say I have a hypothetical network in place, and I want to put, say,
30 diskless Suns (a mix of 3/50's, 3/75's, and 3/110's) and a couple of
servers (3/160's and 3/260's) on it -- is there any way to estimate how much
traffic I'd be generating, assuming a "standard" mix of edits, compiles, a
few Lisps here and there?  What if I wanted to put 100 diskless Suns and
maybe 10 or 15 servers on one ethernet?  500 diskless and 50 servers?  

    In other words, I'd like to be able to figure out just how far can one
push a single ethernet before it gets swamped?  Any useful ideas, either for
measuring the numbers or from experience with large numbers of diskless
machines?  (Sun, are you listening, and can you tell me how this is handled
at SMI?)

    Please reply by mail, and I'll summarize if there's any interest.
-- 
 Matt Landau      	 		BBN Laboratories, Inc.
    mlandau at diamond.bbn.com		10 Moulton Street, Cambridge MA 02238
 ...seismo!diamond.bbn.com!mlandau      (617) 497-2429