Hello,
>
> I am a beginner in ns2 and doing some implementation in ns2 but its giving
> "segmentation fault". Please help me out of this.
> Topology i used is 5 nodes of which 1st one is still and other 4 moving
> towards it with some speed. All the nodes are arranged in a line. And 1st
> node send a communication signal to all the other nodes using multihop.
>
> I am pasting and also attaching the tcl file i used.
> Kindly help.
>
> Regards,
> Vishal
>
> ##code
> # ======================================================================
> # Define options
> # ======================================================================
> set val(chan) Channel/WirelessChannel ;# channel type
> set val(prop) Propagation/TwoRayGround ;# radio-propagation model
> set val(ant) Antenna/OmniAntenna ;# Antenna type
> set val(ll) LL ;# Link layer type
> set val(x) 1000 ;# X dimension of the
> topography
> set val(y) 1000 ;# Y dimension of the
> topography
> set val(ifq) CMUPriQueue ;# Interface queue type
> set val(ifqlen) 50 ;# max packet in ifq
> set val(netif) Phy/WirelessPhy ;# network interface type
> set val(mac) Mac/802_11 ;# MAC type
> set val(adhocRouting) DSR ;# ad-hoc routing protocol
>
> set val(nn) 5 ;# number of mobilenodes
>
>
> # =====================================================================
> # Main Program
> # ======================================================================
>
> #
> # Initialize Global Variables
> #
>
> # create simulator instance
>
> set ns_ [new Simulator]
>
> # setup topography object
>
> set topo [new Topography]
>
> # create trace object for ns and nam
>
> set tracefd [open try1-out.tr w]
> set namtrace [open try1-out.nam w]
>
> $ns_ trace-all $tracefd
> $ns_ namtrace-all-wireless $namtrace $val(x) $val(y)
>
> # define topology
> $topo load_flatgrid $val(x) $val(y)
>
> #
> # Create God
> #
> set god_ [create-god $val(nn)]
>
> #
> # define how node should be created
> #
>
> #global node setting
>
> $ns_ node-config -adhocRouting $val(adhocRouting) \
> -llType $val(ll) \
> -macType $val(mac) \
> -ifqType $val(ifq) \
> -ifqLen $val(ifqlen) \
> -antType $val(ant) \
> -propType $val(prop) \
> -phyType $val(netif) \
> -channel [new $val(chan)] \
> -topoInstance $topo \
> -agentTrace ON \
> -routerTrace ON \
> -macTrace OFF \
> -movementTrace ON
>
> #
> # Create the specified number of nodes [$val(nn)] and "attach" them
> # to the channel.
>
> #Next we create the 5 mobilenodes as follows:
> for {set i 0} {$i < $val(nn) } {incr i} {
> set node_($i) [$ns_ node]
> $node_($i) random-motion 0 ;# disable random motion
> # $node_($i) set Y_ 0.0
> # $node_($i) set Z_ 0.0
> }
>
> #have created mobilenodes, need to give them a position to start with
> $node_(0) set X_ 0.0
> $node_(0) set Y_ 0.0
> $node_(0) set Z_ 0.0
> $node_(1) set X_ 200.0
> $node_(1) set Y_ 0.0
> $node_(1) set Z_ 0.0
> $node_(2) set X_ 400.0
> $node_(2) set Y_ 0.0
> $node_(2) set Z_ 0.0
> $node_(3) set X_ 600.0
> $node_(3) set Y_ 0.0
> $node_(3) set Z_ 0.0
> $node_(4) set X_ 800.0
> $node_(4) set Y_ 0.0
> $node_(4) set Z_ 0.0
>
> #Next producing node movements
> #
> # Node_(1,2,3,4) starts to move towards node_(0)
> #
> $ns_ at 10.0 "$node_(1) setdest 100.0 0.0 1.0"
> $ns_ at 15.0 "$node_(2) setdest 300.0 0.0 1.0"
> $ns_ at 20.0 "$node_(3) setdest 500.0 0.0 1.0"
> $ns_ at 25.0 "$node_(4) setdest 700.0 0.0 1.0"
> #Nodes Movement defined
>
>
> # 1500 - 20 byte IP header - 40 byte TCP header = 1440 bytes
> #Agent/TCP set packetSize_ 1440 ;# This size EXCLUDES the TCP header
> set tcp [new Agent/TCP]
> $tcp set class_ 2
> set sink [new Agent/TCPSink]
> $ns_ attach-agent $node_(0) $tcp
> $ns_ attach-agent $node_(4) $sink
> $ns_ connect $tcp $sink
> set ftp [new Application/FTP]
> $ftp attach-agent $tcp
> $ns_ at 10.0 "$ftp start"
> set agent [new Agent/TCP]
> set app [new Application/FTP]
>
>
>
> # 120 seconds of running the simulation time
> $ns_ at 0.0 "$app start"
>
> #
> # Tell nodes when the simulation ends
> #
> for {set i 0} {$i < $val(nn) } {incr i} {
> $ns_ at 120.0 "$node_($i) reset";
> }
> $ns_ at 120.0001 "stop"
> $ns_ at 120.0002 "puts \"NS EXITING...\" ; $ns_ halt"
> proc stop {} {
> global ns_ tracefd
> $ns_ flush-trace
> close $tracefd
> }
>
> puts "Starting Simulation..."
> $ns_ run
>
>
