[ns] VoIP Packet Size

[Andi Nugroho]

Hai all,
I would like to make a voip packet with the RTP agent and CBR application.
I try to set the payload size on CBR for 33bytes, and the packet size on
RTP agent was 40bytes+33bytes(payload)=73bytes. When i run the simulation
the trace file shows that the CBR packet was 210bytes size. How can i
change the packet size then??
here's my script :

set rtp0 [new Agent/RTP]
$rtp0 set PacketSize 73
$rtp0 set class_ 1
$ns_ attach-agent $n(0) $rtp0
set voip [new Application/Traffic/CBR]
$voip set PacketSize 33
$voip set rate 13.2Kb
$voip set interval 20ms
$voip attach-agent $rtp0
$ns_ at 0.1 "$voip start"
$ns_ at 4.0 "$voip stop"
set null0 [new Agent/LossMonitor]
$ns_ attach-agent $n(1) $null0
$ns_ connect $rtp0 $null0


-- 
Andi Nugroho
Telecommunication&Multimedia,Electrical Eng.
Sepuluh Nopember Technological Institute
Phone  :+6231-60350415
Mobile :+6285648223929
Email  :andi_n at elect-eng.its.ac.id