[ns] two way communication

[Alexander Rasin <alexr@cs.brandeis.edu>]

Hi,

I am trying to implement an Application that will be able to request and
download files through ns simulation.
That requires two way communication between my Applications, and I am
unable to figure out how to do this.

>From what I can tell, one can only attach _one_ Agent to Application.
The only way I can achieve two way communication is through attaching two
agents (TCP and TCPSink) but only one of them can be attached to
application.  Is there a way to attach both of them and be able to
implement the interface that includes both send() and recv() methods?

Thank you
Alex.