virtual connections in Tcl code

[// u l i a n <waldby@uiuc.edu>]

I am testing a new protocol called TACK. I have connected my TACK sender
to the TACK sink, via the command

$ns connect $tsnd0 $tsnk0

Packets sent by the TACK sender are reaching the sink. However, packets
sent by the sink (which are suppose to be ACKs destined for the sender)
seem to have destination $tsnk0, so they are not going anywhere. When I
set up a Ping protocol previously, the connect command was sufficient
for two-way communication. Why would the TACK sink be sending to itself
and not to the sender?

Thanks for any help.

Julian Waldby
University of Illinois