RE: Traffic characteristics
Expanding on some of these points. Yes, self-similar traffic is a
good way to go to simulate large amounts of IP traffic.
Self-similar traffic models are already available that allow you to
bypass modelling of the TCP/IP stack (although, I believe that BJ has
some concerns in this regard). Bo Ryu from Hughes Research Labs has
done extensive research in this area. I can put people in touch
with him if they are interested.
In my opinion, there should be a series of scenarios that test different
aspects of the system. Perhaps, self-similar traffic is one test
for the performance of TCP/IP traffic. It is also possible to get
models of live traffic to play over the models, as well as, standard
application traffic models such as HTTP, FTP, e-mail, video, voice,
etc. I agree with Raj in that a determination of typical traffic
mixes needs to be made, and different scenarios constructed to model
these mixes. My opinion does differ from Raj, however, in that I
think pathological cases can provide as much insight into system behavior
as typical cases and scenarios should be constructed for both,
particularly for a protocol where one of the main goals is resiliency in
the face of link failure.
Taylor
At 06:25 PM 8/23/00 -0700, Raj Sharma wrote:
- You could use self similar traffic patterns.
There is quite a bit of publication on such traffic
patterns. William Stallings had a book that spent an entire
section on it. (High performance networks ---- or something
like that)
However, isnt this more of a "regression" parameter
rather than "main" parameters we want to test our
Layer 2 protocol against. Much of the issue that
we need to sort out for these main parameters
are the ranges of value. Cooking up these values must
make practical sense and they cannot be pathological
cases to test boundary conditions.
Perhaps what we need to do is to move one level up
and ask ourselves what services will get provisioned
over (layer 2) RPR and hence what are the main parameters.
Remember you cant design a layer 2 protocol only
based on a specific layer 3 protocol. If that is the case, I rather
do MPLS switching over rings.
Thoughts?
-----Original Message-----
From: Khaled Amer
[mailto:khaledamer@xxxxxxx]
Sent: Thursday, August 24, 2000 3:23 AM
To: Reflector RPRSG
Subject: Traffic characteristics
RPR'ers,
I raised this question about 3 weeks ago and got the familiar
underwhelming response!
Several people indicated availability of traffic patterns that were
taken off the Internet or other networking environments that would be
useful for us to use in the simulations. In my mind, we need things like
packet size distributions, interarrival times, burstiness, application
and protocol distributions, and any other relevant characteristics of
network traffics that we may want to consider in the simulations.
Does anyone have such information that they can share with us in the
meeting next week?
Khaled Amer
President,
AmerNet
Architecture Analysis and Performance Modeling Specialists
Phone:
(949)552-1114
13711 Solitaire Way, Irvine, CA 92620
Fax:
(949)552-1116
e-mail:
khaledamer@xxxxxxx
**********************************************************************
P. Taylor
Salman Phone:
202-364-4700x2297
Manager, Market
Research Mobile:
202-427-3319
OPNET Technologies,
Inc. E-mail:
tsalman@xxxxxxxxx
Washington, DC 20008
**********************************************************************