[ns] otcl script for broadcast

[Phenix]

Hi guys,

Can you tell how to write tcl script for broadcast?
In unicasti, we can generally do as follows:

set udp_(0) [new Agent/UDP]
$ns_ attach-agent $node_(0) $udp_(0) 

set null_(0) [new Agent/Null]
$ns_ attach-agent $node_(1) $null_(0)

$ns_ connect $udp_(0) $null_(0)
set cbr_(0) [new Application/Traffic/CBR]
$cbr_(0) attach-agent $udp_(0)

However, it's only a point-to-point way.  
How should I deal with broadcast in which scenario only one
node send packets and all of the others receive.

Waiting for your help. Thanks ! 

Regards,
Phenix