[Click] nsclick + tracefile strangeness

[David Bath]

Hey list,

I was hoping someone might give me a few pointers on this.

I've got two Agents attached to sources (as far as I can see in a pretty
similar manner to the nsclick example paper), as follows:

Agent/Null set sport_		5000
Agent/Null set dport_		5000

Agent/CBR set sport_		5000
Agent/CBR set dport_		5000

set source_startxmittime 1
set source_xmitrate 400
set source_xmitinterval 0.1
set source_packetsize 64

set raw_(0)		[new Agent/Raw]
set null_(0)	[new Agent/Null]

$ns_ attach-agent $node_(0) $raw_(0)	
$ns_ attach-agent $node_(3) $null_(0)

# Set up a raw channel between node0 and node3
$raw_(0) set-srcip [$node_(0) getip eth0]
$raw_(0) set-srcport 5000	
$raw_(0) set-destip [$node_(3) getip eth0]
$raw_(0) set-destport 5000
$raw_(0) set fid_ 1

# Set up a CBR and attach it to the RAW 
set cbr_(0) [new Application/Traffic/CBR]
$cbr_(0) set packetSize_ $source_packetsize
$cbr_(0) set interval_ $source_xmitinterval
$cbr_(0) set random_ 0
$cbr_(0) set maxpkts_ [expr ( $sim(stoptime) - $source_startxmittime ) *
$source_xmitrate]
$cbr_(0) attach-agent $raw_(0)


$ns_ at $source_startxmittime "$cbr_(0) start"

However, I'm a bit confused about what I'm seeing in my trace file.
Essentially, I'm certainly not seeing pairs of AGT send and receive as I
would expect.  In fact, the first thing I see is a receive on node3  -
but before there are any AGT sends!

I'm using the simple flat arp-querier click definition, and I can
happily see each packet (on port 5000) being sent tokernel and received
fromkernel.  I just seem to be having some difficulty accounting it in
ns.  

If anyone has had any experience in this, I'd be most grateful for some
insight.

Best Regards,

Dave Bath
University of Bristol