Simulation of IEEE 802.15.4 (WPAN) in NS-2

To simulate 802.15.4, we just need two commands.

1. $node sscs startPANCoord <txBeacon = 1> <beaconOrder = 3>  <SuperframeOrder = 3>

This command can be used to start a PAN coordinator. Generally, there will be only one coordinator in a PAN.  If some parameters are omitted, the default values shown above will be assumed.

– Examples:

• $node_(0) sscs startPANCoord

• $node_(0) sscs startPANCoord 1 3 3

2. $node sscs startDevice <isFFD = 1> <assoPermit = 1> <txBeacon = 0> <beaconOrder = 3> <SuperframeOrder = 3>

 This Command can be used to start a device or coordinator. If some parameters are omitted, the default values shown above will be assumed.

– Examples:

• $node_(0) sscs startDevice // non-beacon

• $node_(0) sscs startDevice 1 1 1 // beacon enabled

Following is the simple tcl script to simulate IEEE 802.15.4. It consists of only two nodes; 1 coordinator and 1 end node.

==================================Start=================================

set stopTime 100

set BO 3

set SO 3

set speed 1

#speed is in m/s

# ======================================================================

# Define options

# ======================================================================

set val(chan)        Channel/WirelessChannel    ;# Channel Type

set val(prop)        Propagation/TwoRayGround   ;# radio-propagation model

set val(netif)         Phy/WirelessPhy/802_15_4

set val(mac)         Mac/802_15_4

set val(ifq)           Queue/DropTail/PriQueue    ;# interface queue type

set val(ll)             LL                         ;# link layer type

set val(ant)          Antenna/OmniAntenna        ;# antenna model

set val(ifqlen)      50                         ;# max packet in ifq

set val(nn)          2                         ;# number of mobilenodes

set val(rp)          AODV                       ;# routing protocol

set val(x)           50

set val(y)           50

set opt(err)        UniformErrorProc

set val(nam)                2nodes.nam

set val(traffic) cbr                        ;# cbr/poisson/ftp

#read command line arguments

proc getCmdArgu {argc argv} {

        global val

        for {set i 0} {$i < $argc} {incr i} {

                set arg [lindex $argv $i]

                if {[string range $arg 0 0] != "-"} continue

                set name [string range $arg 1 end]

                set val($name) [lindex $argv [expr $i+1]]

        }

}

getCmdArgu $argc $argv

##This is optional error model. you can delete it if u dont need it

proc UniformErrorProc {} {

#          puts "useing error model-"

            set err [new ErrorModel]

#          $err unit pkt

            $err set rate_ 0.05

            return $err

}

# Initialize Global Variables

set ns_             [new Simulator]

set tracefd     [open ./2nodes.tr w]

$ns_ trace-all $tracefd

if { "$val(nam)" == "2nodes.nam" } {

       set namtrace     [open ./$val(nam) w]

        $ns_ namtrace-all-wireless $namtrace $val(x) $val(y)

}

$ns_ puts-nam-traceall {# nam4wpan #}                   ;# inform nam that this is a trace file for wpan (special handling needed)

#Mac/802_15_4 wpanNam macType $para1  # added by pranesh

Mac/802_15_4 wpanCmd verbose on

Mac/802_15_4 wpanNam namStatus on                   ;# default = off (should be turned on before other 'wpanNam' commands can work)

#Mac/802_15_4 wpanNam ColFlashClr gold             ;# default = gold

# For model 'TwoRayGround'

set dist(5m)  7.69113e-06

set dist(9m)  2.37381e-06

set dist(10m) 1.92278e-06

set dist(11m) 1.58908e-06

set dist(12m) 1.33527e-06

set dist(13m) 1.13774e-06

set dist(14m) 9.81011e-07

set dist(15m) 8.54570e-07

set dist(16m) 7.51087e-07

set dist(20m) 4.80696e-07

set dist(25m) 3.07645e-07

set dist(30m) 2.13643e-07

set dist(35m) 1.56962e-07

set dist(40m) 1.20174e-07

Phy/WirelessPhy set CSThresh_ $dist(15m)

Phy/WirelessPhy set RXThresh_ $dist(15m)

# set up topography object

set topo       [new Topography]

$topo load_flatgrid $val(x) $val(y)

#ns-random 1  gives same result in trace file everytime simulation is done

#ns-random 0 gives different result in trace file when simulated

ns-random 0

# Create God

set god_ [create-god $val(nn)]

set chan_1_ [new $val(chan)]

# configure node

$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) \

                        -topoInstance $topo \

                        -agentTrace ON \

                        -routerTrace OFF \

                        -macTrace ON \

                        -movementTrace OFF \

                        -energyModel "EnergyModel" \

                        -initialEnergy 10 \

                        -idlePower 0.00279 \

                        -rxPower 0.0565 \

                        -txPower 0.048 \

                        -sleepPower 0.000030 \

                        -transitionPower 0.002 \

                        -transitionTime 0.0002 \

                        -IncomingErrProc $opt(err) \

                        -channel $chan_1_ 

for {set i 0} {$i < $val(nn) } {incr i} {

            set node_($i) [$ns_ node]      

            $node_($i) random-motion 0             ;# disable random motion

}

##initial postion of node 0 and node 1

$node_(0) set X_ 25.0

$node_(0) set Y_ 25.0

$node_(0) set Z_ 0.0

$node_(1) set X_ 10.0

$node_(1) set Y_ 25.0

$node_(1) set Z_ 0.0

$ns_ at 0.0  "$node_(0) NodeLabel PAN Coor"

$ns_ at 0.0  "$node_(0) sscs startPANCoord 1 $BO $SO"  ;# startPANCoord <txBeacon=1> <BO=3> <SO=3>

$ns_ at 5  "$node_(1) sscs startDevice 0 0 0 $BO $SO"

Mac/802_15_4 wpanNam PlaybackRate 3ms

$ns_ at 50 "puts \"\nTransmitting data ...\n\""

##define traffic type and date rate 

set udp_(0) [new Agent/UDP]

$ns_ attach-agent $node_(1) $udp_(0)

set null_(0) [new Agent/Null]

$ns_ attach-agent $node_(0) $null_(0)

set cbr_ [new Application/Traffic/CBR]

$cbr_ set packetSize_ 100

$cbr_ set interval_ 0.2

$cbr_ set random_ 1

$cbr_ attach-agent $udp_(0)

$ns_ connect $udp_(0) $null_(0)

$ns_ at 50 "$cbr_ start"

# the following command is for moving the node 1. you can disable it if you dont need it.

#node 1 will start to meet at time 70 towards the cordinate(42,25) at the speed of $speed. $speed is defined at top.

$ns_ at 70 "$node_(1) setdest 42.00 25 $speed"

# defines the node size in nam

for {set i 0} {$i < $val(nn)} {incr i} {

            $ns_ initial_node_pos $node_($i) 2

}

# Tell nodes when the simulation ends

for {set i 0} {$i < $val(nn) } {incr i} {

    $ns_ at $stopTime "$node_($i) reset";

}

##to stop simulation

$ns_ at $stopTime "stop"

$ns_ at $stopTime "puts \"\nNS EXITING...\n\""

$ns_ at $stopTime "$ns_ halt"

proc stop {} {

    global ns_ tracefd appTime val env

    $ns_ flush-trace

    close $tracefd

    set hasDISPLAY 0

    foreach index [array names env] {

        if { ("$index" == "DISPLAY") && ("$env($index)" != "") } {

                set hasDISPLAY 1

        }

    }

}

puts "\nStarting Simulation..."

$ns_ run

===========================End====================

Extra Features in the TCL

In the above two extra features have been added as bonus. 

1. Error model

Error model has been added in the tcl file. UniformErrorProc defines the error mode and error rate. The error rate is set to 5%. If someone don’t need error model you can delete the UniformErrorProc. But make sure you delete “-IncomingErrProc $opt(err) \”  from node-config function also.

2. Setdest

Setdest has been used in the tcl file. Setdest function is use for node mobility. Setdest is used to move node from current position to new position.

The syntax is:

 $node_(1) setdest  newXpos newYpos speed

for example: setdest 50 50 2 ;  will move node 1 from current location to 50,50 at the speed of 2 m/s.

You can disable the node movement by just delete the setdest line.

P.S. Queries are welcome. I will try to answer to my earliest convince. Thank you.