starting the mobile nodes at any given time

[Maria Papadopouli <maria@cs.columbia.edu>]

Hello to all:

I was wondering if you have any suggestion on the following problem:
I am simulating a protocol related to the mobile/wireless networks 
using ns-2/cmu-extension and each mobile node starts participating in the 
protocol (broadcasting pkts/respond to msgs, etc) at a specified time $t$ (the time may be different for each node).

However, i would like to force the mobile node not to receive any pkts, 
if it is not participating in the protocol.

I thought that a natural approach is the following:

# configure node
         $ns_ node-config -adhocRouting $opt(rp)\
                         -llType $opt(ll) \
                         -macType $opt(mac) \
                         -ifqType $opt(ifq) \
                         -ifqLen $opt(ifqlen) \
                         -antType $opt(ant) \
                         -propType $prop \
                         -phyType $opt(netif) \
                         -channelType $channel \
                         -topoInstance $topo \
                         -agentTrace ON \
                         -routerTrace ON \
                         -macTrace ON \
                         -movementTrace ON

 $ns_ at 5.0 "set node_(1) [$ns_ node]"

(assuming that at time 5.0 the node_(1) starts participating in the protocol)

but this gives me problems in tcl, because when later i have
something of the sort: 
$ns_ at 5.653178417 "$node_(1) set Z_ 0"

ns gives me error:

> can't read "node_(1)": no such variable
>     while executing
> "$ns_ at 5.653178417 "$node_(1) set Z_ 0""

I mentioned that to the monarch project, at CMU, and they told me that
in their version the above works fine.
Would this be a bug in the VINT version?

As an alternative, i also tried to set initially the rxPower and txPower to 0.0
and set up to a different number later when a node
starts participating in the protocol. However, that didn't work either ...
The node could still receive the pkts (even that its rxPower was 0).

Do you have any idea/suggestion how to solve this problem.

Thanks  a lot!

Maria Papadopouli
---
Computer Science Dept.
Columbia University
New York, NY10027
http://www.cs.columbia.edu/~maria/