Background traffic

[Hemon Bruno <bruno@CS.UCLA.EDU>]

I am studying the behavior of several TCP connections sharing the same
bottleneck. 
I need to have a sort of background traffic, to introduce some packet
losses and some randomness.
I was thinking of using a UDP traffic source but I don't know really how
to choose the parameters. 
Do you have any idea of how to simulate a background traffic, whose
characteristics would be representative of the Internet traffic ?

Thanks,

                Bruno 

+------------------------------------------+
| Bruno HEMON           bruno@cs.ucla.edu  |
|                                          |
| Graduate Student                         |
| Computer Science Department              |
| University of California at Los Angeles  |
|                                          |
| Promotion 97                             |
| Ecole Centrale Paris                     |
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