[ns] Droptail queue per-flow rate limiting using TokenBucket (or other mechanism?)

[Prajjwal Devkota]

Hi list,

I am currently doing some ethernet level rate limiting simulations using
ns-2.  I had been doing my simulations with a simple DropTail queue (by
physically changing the link rate), but now, I am trying to see if I can
apply a Token Bucket implementation to support multiple flows in a simple
manner.  I have been searching the mailing list to I can find pointers on
getting started, as well as some of the ns-2 code (using a source browser),
but I have generally only found references to Diffserv.  I did notice that
ns-2 does have a TokenBucket class implemented though.  However, as far as I
can see, diffserv seems to be the only one referencing this class.

I came across this discussion on the ns users mailing list at
http://mailman.isi.edu/pipermail/ns-users/2005-June/050699.html
  and the conclusion seems to be that using Diffserv with the queue mode
being specified as DropTail was what a solution.

My rate limiting simply requires token bucket mechanism: once I know the
flow-id, I will have to do token bucket rate limiting myself.  As per my
understanding, diffserv is a class based qos mechanism, not a flow based
one.  Is looking into diffserv a good choice, or is there a better solution,
or one that might be more appropriate for my requirements?

I would appreciate any pointers that you could offer on this.

Thank you very much for your help!