[ns] reg error : ap lookup failed

[Karthik Talloju]

I am trying to run infra.tcl that is present in the examples of ns2.
(Location : /ns2.3/ns-2.33/tcl/ex/802.11/infra.tcl)
I find a lot of errors among which one of them is : ap lookup failed.

I am unable to figure out any mistakes in the code(it is an example,  
theres no mistake in the code, i would think) and how to get it  
running. Any help is greatly appreciated. Thank you.

Karthik 


Following is the code, if someone is unable to locate it :

#**********************************************************
set val(chan)           Channel/WirelessChannel    ;#Channel Type
set val(prop)           Propagation/TwoRayGround   ;# radio- 
propagation model
set val(netif)          Phy/WirelessPhy            ;# network  
interface type
set val(mac)            Mac/802_11                 ;# MAC type
set val(ifq)            Queue/DropTail             ;# 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)             10                         ;# number of  
mobilenodes
set val(rp)             DumbAgent                  ;# routing protocol
set val(x)              600
set val(y)              600

Mac/802_11 set dataRate_ 11Mb

#Phy/WirelessPhy set CSThresh_ 10.00e-12
#Phy/WirelessPhy set RXThresh_ 10.00e-11
#Phy/WirelessPhy set Pt_ 0.1
#Phy/WirelessPhy set Pt_ 7.214e-3

# Initialize Global Variables
set ns_         [new Simulator]
set tracefd     [open infra.tr w]
$ns_ trace-all $tracefd


# set up topography object
set topo       [new Topography]

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

# Create God
create-god $val(nn)

# Create channel
set chan_1_ [new $val(chan)]


$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 OFF \
                -routerTrace OFF \
                -macTrace ON \
                -movementTrace ON \
                -channel $chan_1_


       for {set i 0} {$i < [expr $val(nn)]} {incr i} {
                   set node_($i) [$ns_ node]
                
                 $node_($i) random-motion 0              ;# disable  
random motion
                set mac_($i) [$node_($i) getMac 0]


                $mac_($i) set RTSThreshold_ 3000
                
                $node_($i) set X_ $i
                $node_($i) set Y_ 0       ;# Horizontal arrangement of nodes
                $node_($i) set Z_ 0.0
                
        }

#Set Node 0 and Node $val(nn) as the APs. Thus the APs are the ends of  
the horizontal line. Each STA receives different power levels.


set AP_ADDR1 [$mac_(0) id]
$mac_(0) ap $AP_ADDR1
set AP_ADDR2 [$mac_([expr $val(nn) - 1]) id]
$mac_([expr $val(nn) - 1]) ap $AP_ADDR2

#$mac_([expr $val(nn) - 1]) set BeaconInterval_ 0.2


$mac_(1) ScanType ACTIVE

for {set i 3} {$i < [expr $val(nn) - 1]} {incr i} {
        $mac_($i) ScanType PASSIVE      ;#Passive
}


$ns_ at 1.0 "$mac_(2) ScanType ACTIVE"

Application/Traffic/CBR set packetSize_ 1023
Application/Traffic/CBR set rate_ 256Kb

        
for {set i 1} {$i < [expr $val(nn) - 1]} {incr i} {
        set udp1($i) [new Agent/UDP]

        $ns_ attach-agent $node_($i) $udp1($i)
        set cbr1($i) [new Application/Traffic/CBR]
        $cbr1($i) attach-agent $udp1($i)
}


set base0 [new Agent/Null]

$ns_ attach-agent $node_(1) $base0

set base1 [new Agent/Null]

$ns_ attach-agent $node_(8) $base1

$ns_ connect $udp1(4) $base0
$ns_ connect $udp1(5) $base1


$ns_ at 2.0 "$cbr1(4) start"

$ns_ at 4.0 "$cbr1(5) start"

$ns_ at 10.0 "$node_(4) setdest 300.0 1.0 30.0"

$ns_ at 20.0 "stop"
$ns_ at 20.0 "puts \"NS EXITING...\" ; $ns_ halt"

proc stop {} {
     global ns_ tracefd
     $ns_ flush-trace
     close $tracefd
     exit 0
}

puts "Starting Simulation..."
$ns_ run

#**********************************************************