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Bug in QueueMonitoring with multicast traffic?



Hello ns-users,

I'm running ns-2.1b2 and have I experienced a problem with queue monitoring. 
It appears to me that parrivals_ and barrivals_ are not taken care of properly 
when routing multicast traffic. I ran tests with two different kinds of 
multicast traffic (SRM and my own creation MFTP) and in both cases, multicast 
data packets were not counted in "parrivals_". I also found that all works 
fine with unicast packets.

Attached to this mail is a simple test script that creates the following 
network:


   n0 <--------> n1 <--------> n2 <--------> n3
  SRM                                        SRM
 with CBR

An Agent/SRM with CBR as traffic source is attached to node n0, and
node n3 runs a (passive) SRM receiver. Link n1->n2 is to be monitored:


The output after some seconds of simulation yields the following:

Link statistics for link n1->n2:
parrivals_=0, pdrops_=27, pdepartures_=198
barrivals_=0, bdrops_=27000, bdepartures_=105512

This doesn't look right, does it? Could somebody fix the problem?


   Thanks,

        -Chris.


test.ns