Tcl script to create the dynamic number of nodes and its initial location NS2 WIRELESS PROGRAM

Description:

      Number of nodes is not fixed in the program. We can give the number of nodes to be created during runtime. Number of nodes should be given as command line arguments when we run the coding. Dynamically created nodes are configured with specific parameters of a mobile wireless node. After creating the nam file and trace file, we set up topography object. set node_ ($i) [$ns node] is used to create the nodes. Initial location of the nodes is not fixed. X, Y coordinates are randomly selected and assigned to every node. Here we set the initial size for the every node by using initial_node_pos. AODV routing protocol is used here. $val(stop) specifies the end time of the simulation. In this program nodes are given with yellow color.

File name: “wireless3.tcl”

#-------Event scheduler object creation--------#
set ns [new Simulator]
#creating the trace file and nam file
set tracefd [open wireless3.tr w]
set namtrace [open wireless3.nam w]   
$ns trace-all $tracefd
$ns namtrace-all-wireless $namtrace $val(x) $val(y)
# set up topography object
set topo       [new Topography]
$topo load_flatgrid $val(x) $val(y)
set god_ [create-god $val(nn)]
# configure the nodes
        $ns node-config -adhocRouting $val(rp) \
                   -llType $val(ll) \
                   -macType $val(mac) \
                   -ifqType $val(ifq) \
                   -ifqLen $val(ifqlen) \
                   -antType $val(ant) \
                   -propType $val(prop) \
                   -phyType $val(netif) \
                   -channelType $val(chan) \
                   -topoInstance $topo \
                   -agentTrace ON \
                   -routerTrace ON \
                   -macTrace OFF \
                   -movementTrace ON
## Creating node objects..               
      for {set i 0} {$i < $val(nn) } { incr i } {
            set node_($i) [$ns node]     
      }
      for {set i 0} {$i < $val(nn) } {incr i } {
            $node_($i) color gold
            $ns at 0.0 "$node_($i) color gold"
      }
## Provide initial location of mobilenodes..
            for {set i 0} {$i < $val(nn) } { incr i } {
                  set xx [expr rand()*600]
                  set yy [expr rand()*600]
                  $node_($i) set X_ $xx
                  $node_($i) set Y_ $yy
                 
            }
     
# Define node initial position in nam
for {set i 0} {$i < $val(nn)} { incr i } {
# 30 defines the node size for nam
$ns initial_node_pos $node_($i) 30
}
# Telling nodes when the simulation ends
for {set i 0} {$i < $val(nn) } { incr i } {
    $ns at $val(stop) "$node_($i) reset";
}
# ending nam and the simulation
$ns at $val(stop) "$ns nam-end-wireless $val(stop)"
$ns at $val(stop) "stop"
$ns at 10.01 "puts \"end simulation\" ; $ns halt"
#stop procedure...
proc stop {} {
    global ns tracefd namtrace
    $ns flush-trace
    close $tracefd
    close $namtrace
exec nam wireless3.nam &
}
$ns run
# How to run the program
$ns wireless3.tcl
# snapshot of the program output