Remember to set the bandwidth in Mbps. The following paragraph is part of
the chapter 3.2 of the ns2 manual:
Bandwidth is specified as a real value, optionally suffixed by a 'k' or 'K'
to mean kilo-quantities, or 'm' or 'M' to mean
mega-quantities. A final optional suffix of 'B' indicates that the quantity
expressed is in Bytes per second. The default
is bandwidth expressed in bits per second. For example, all of the following
are equivalent:
$object set bwvar 1.5m
$object set bwvar 1.5mb
$object set bwvar 1500k
$object set bwvar 1500kb
$object set bwvar .1875MB
$object set bwvar 187.5kB
$object set bwvar 1.5e6
Guillermo Biot
>Hello,
>
>Did you get the answer to your reply? I'm asking because I am also
experiencing the same problem with the throughput.
>Please help me if you have a solution.
>
>Also please tell me the version you are using. Mine is ns 2.28.
>
>Thanks a lot,
>Kamil
>
>Sandeep-9 wrote:
>
>
>>Hi
>> In the below code whatever Mac/802_11 parameters I set are not taking
>>effect. For instance eventhough I set _dataRate 11mbps, throughput is
>>coming around 400kbps, which is the default rate for udp. If I change
>>_dataRate, basicRate_ or PLCPDataRate_ , there is absolutely no effect.
>>Please if anyone can help, because I require them in my work.
>>Thanks in advance,
>>regards,
>>Sandeep.
>> 1 set val(chan) Channel/WirelessChannel ;# channel type
>> 2 set val(prop) Propagation/TwoRayGround ;#
>>radio-propagation model
>> 3 set val(netif) Phy/WirelessPhy ;# network
>>interface type
>> 4 set val(mac) Mac/802_11 ;# MAC type
>> 5 set val(ifq) Queue/DropTail/PriQueue ;# interface queue
>>type
>> 6 set val(ll) LL ;# link layer type
>> 7 set val(ant) Antenna/OmniAntenna ;# antenna model
>> 8 set val(ifqlen) 50 ;# max packet in ifq
>> 9 set val(nn) 2 ;# number of
>>mobilenodes
>> 10 set val(rp) DSDV ;# routing protocol
>> 11 set val(x) 800
>> 12 set val(y) 800
>> 13
>> 14 Phy/WirelessPhy set bandwidth_ 11Mb
>> 15
>> 16 Mac/802_11 set SlotTime_ 0.000020 ;# 20us
>> 17 Mac/802_11 set SIFS_ 0.000010 ;# 10us
>> 18 Mac/802_11 set PreambleLength_ 144 ;# 144 bit
>> 19 Mac/802_11 set PLCPHeaderLength_ 48 ;# 48 bits
>> 20 Mac/802_11 set PLCPDataRate_ 1.0 ;# 1Mbps
>> 21 Mac/802_11 set dataRate_ 11.0 ;# 11Mbps
>> 22 Mac/802_11 set basicRate_ 1.0 ;# 1Mbps
>> 23
>> 24 set ns [new Simulator]
>> 25 set tr [open trace.tr w]
>> 26 $ns trace-all $tr
>> 27 set na [open trace.nam w]
>> 28 $ns namtrace-all-wireless $na $val(x) $val(y)
>> 29 set chan1 [new $val(chan)]
>> 30 set topo [new Topography]
>> 31 $topo load_flatgrid 500 500
>> 32 create-god 2
>> 33
>> 34 proc finish {} {
>> 35 global ns tr na
>> 36 $ns flush-trace
>> 37 $ns nam-end-wireless [$ns now]
>> 38 close $tr
>> 39 close $na
>> 40 exec nam trace.nam &
>> 41 exit 0;
>> 42 }
>> 43
>> 44 $ns node-config -adhocRouting $val(rp)\
>> 45 -llType $val(ll) \
>> 46 -macType $val(mac) \
>> 47 -antType $val(ant) \
>> 48 -propType $val(prop) \
>> 49 -phyType $val(netif) \
>> 50 -channel $chan1 \
>> 51 -topoInstance $topo \
>> 52 -agentTrace ON \
>> 53 -routerTrace ON \
>> 54 -macTrace ON \
>> 55 -movementTrace OFF\
>> 56 -ifqType $val(ifq) \
>> 57 -ifqLen $val(ifqlen)
>> 58
>> 59 for {set i 0} {$i < 2} {incr i} {
>> 60 set node_($i) [$ns node]
>> 61 $node_($i) random-motion 0
>> 62 }
>> 63
>> 64 $node_(0) set X_ 0
>> 65 $node_(0) set Y_ 0
>> 66 $node_(0) set Z_ 0
>> 67 $node_(1) set X_ 10
>> 68 $node_(1) set Y_ 0
>> 69 $node_(1) set Z_ 0
>> 70
>> 71 $node_(0) color green
>> 72 $node_(1) color green
>> 73
>> 74 set udp [new Agent/UDP]
>> 75 set des [new Agent/Null]
>> 76 $ns attach-agent $node_(0) $udp
>> 77 $ns attach-agent $node_(1) $des
>> 78 $ns connect $udp $des
>> 79
>> 80 set udapp [new Application/Traffic/CBR]
>> 81 $udapp attach-agent $udp
>> 82 $udapp set fid_ 1
>> 83 $udapp set packetSize_ 400
>> 84
>> 85 $ns at 1.0 "$udapp start"
>> 86 $ns at 30.0 "$udapp stop"
>> 87 $ns at 30.0 "$ns halt"
>> 88 ns at 30.0 "finish
>> 89 $ns run"
>>
>>
>>
>>
>>
>Quoted from:
>
http://www.nabble.com/why-does-the-code-below-doesn%27t-work-as-expected-tf2188094.html#a6053421
>
>
>
Hi Kamil,
My problem is solved, there was an error in through calculation,
instead of calculating recieve events at destination node, I was
calculating recieve at RTR agent in source node itself. Hence I was
calculating sending rate not throughput, there was no actual
transmission because I didn't set phy parameters in script. I sending
those parameters. As I have already simulated it, u ask me if u have any
other doubt. The parameters below are for 11g.
Antenna/OmniAntenna set Gt_ 1
Antenna/OmniAntenna set Gr_ 1
Phy/WirelessPhy set L_ 1.0
Phy/WirelessPhy set freq_ 2.472e9
Phy/WirelessPhy set Pt_ 0.031622777
Phy/WirelessPhy set CPThresh_ 10.0
Phy/WirelessPhy set CSThresh_ 5.011872e-12
Phy/WirelessPhy set RxThresh_ 5.82587e-09 ;#Receive power
threshold calculated under TwoRay ground model
Phy/WirelessPhy set Rb_ 2*1e6
Mac/802_11 set RTSThreshold_ 3000 ;#To suppress RTS/CTS Packets
increase the rts threshold
