Asymmetric Link???

[harlisya@erg.abdn.ac.uk (Harlisya Harun)]

Hi,
	I am a bit confuse about these two terms: Asymmetric and Source Asymmetric, for example:

if { $type == "asym" } {
	set tcp [createTcpSource "TCP/Asym" $maxburst $tcpTick]
	set sink [ceateTcpSink "TCPSink/Asym" $sinktrace $ackSize $maxdelack]
elseif { $type == "asymsrc" } {
	set tcp [createTcpSource "TCP/Asym" $maxburst $tcpTick]
	set sink [ceateTcpSink "TCPSink" $sinktrace $ackSize $maxdelack]
}

Let say, my topology is:

	  10 Mb    10 Mb    10 Mb
	n0------r1-------r2-------n1
		   28.8 Kb


So, which is the correct asymmetric term, then????? "asym" or "asymsrc"????

Another puzzle is to attach the agent..... Since the asymmetric link is only occurs from r1 to r2, so do we need to assume the whole link is an asymmetric link, by putting asymmetric sender on node $n0, such that: $ns attach-agent $n0 $tcp  , and for the receiver: $ns attach-agent $n1 $sink ?????

OR, do weed need to separate to two sender and receiver by creating another agent for n0  and n1, and of course, an asymmetric agent for r1 and r2 ????

Your cooperation is highly  appreciated.  Thank you.


Regards,
harlisya