TCL File in Ns2

            The Tcl scripts are deployed in Ns2 simulator tools and they are utilized to setup the wired and wireless communication network and it is functioning for the scripts through Ns2 to acquire the simulation results.

Trace Files Generated in Ns2 Using Tcl

             Ns2 is functioning as the support for various types of trace files and it includes the Nam trace format that includes the required information in simulation to drive the Nam visualizer process and it is to trace the formats in all the aspects based on Ns2 simulation. The process of tracing and monitoring is considered as the representation of data collection in Ns2.

            Additionally, we have highlighted the processes that are required to learn the program based the utilization of Tcl in the following.

Learn to Program Using Tcl

  • A simulator is created using the following Tcl code
Set nssim [new simulator]
  • The size of the area is defined in which simulation is preceded and we have to define the position of nodes in the network based on the size
settopo [new Topography]
$topoload_flatgrid $val(x) $val(y)
  • It is deployed to record the events that are occurring in the simulation
Set tracef [open results.tr w]
$ nssimtrace-all $tracef
  • Next, GOD is deployed to store the global information about the network, nodes and state of environment

Create-god (1)

  • The below mentioned commands are deployed to create and configure AP/BS using TCL
Set ap_name [$nssimap]
To configure AP/BS:
$nssimap-config –optn_1 val_1\
………………………………… –optn_nval_n

          With some knowledge about the functions of implementing Tcl code, our research professionals are highlighted the significant research process that is about the simulation of IEEE 802.11p MAC protocol in Ns2.

Tcl Code to Simulate IEEE 802.11p MAC Protocol in Ns2

# Change Phy and Mac
set val(netif) Phy/WirelessPhyExt
;# network interface type
set val(mac) Mac/802_11Ext
;# MAC type
# 802.11p parameters
Phy/WirelessPhyExt set CSThresh_ 3.9810717055349694e-13
;# -94 dBm wireless interface sensitivity
Phy/WirelessPhyExt set Pt_ 0.002
;# equals 20dBm when considering antenna gains of 1.0
Phy/WirelessPhyExt set freq_ 5.9e+9
Phy/WirelessPhyExt set noise_floor_ 1.26e-13 ;
# -99 dBm for 10MHz bandwidth
Phy/WirelessPhyExt set L_ 1.0
;# default radio circuit gain/loss Phy/WirelessPhyExt set PowerMonitorThresh_ 3.981071705534985e-18 ;
# -174 dBm power monitor sensitivity (=level of gaussian noise) Phy/WirelessPhyExt set HeaderDuration_ 0.000040 ;
# 40 us Phy/WirelessPhyExt set BasicModulationScheme_ 0 Phy/WirelessPhyExt set PreambleCaptureSwitch_ 1 Phy/WirelessPhyExt set DataCaptureSwitch_ 1 Phy/WirelessPhyExt set SINR_PreambleCapture_ 3.1623;
;# 5 dB Phy/WirelessPhyExt set SINR_DataCapture_ 10.0; ;
# 10 dB Phy/WirelessPhyExt set trace_dist_ 1e6
;# PHY trace until distance of 1 Mio. km ("infinity") Phy/WirelessPhyExt set PHY_DBG_ 0 Mac/802_11Ext set CWMin_ 15 Mac/802_11Ext set CWMax_ 1023 Mac/802_11Ext set SlotTime_ 0.000013 Mac/802_11Ext set SIFS_ 0.000032 Mac/802_11Ext set ShortRetryLimit_ 7 Mac/802_11Ext set LongRetryLimit_ 4 Mac/802_11Ext set HeaderDuration_ 0.000040 Mac/802_11Ext set SymbolDuration_ 0.000008 Mac/802_11Ext set BasicModulationScheme_ 0 Mac/802_11Ext
set use_802_11a_flag_ true Mac/802_11Ext set RTSThreshold_ 2346 Mac/802_11Ext
set MAC_DBG
0

First Tcl

         Here, we are providing the guidance to write a template that is capable for the users to utilize for all of the first Tcl scripts. The researchers can write the Tcl scripts in any text editor including the joe, emacs and etc. Our research professionals are suggesting that the researchers call this first example “example1.tcl”.  Initially, we have to create a simulator object using the following command,

set ns [new Simulator]

          Consequently, we have to open a file to write which is going to be deployed for the nam trace data through the command that is mentioned below.

set nf [open out.nam w]
$ns namtrace-all $nf

            The first command is about the releases of file “out.nam” which is deployed to write and it provides the file handle “nf”. Through the following command, we provide the simulator object what we have created above to write all simulation data and it is relevant for nam into this file.  Following that, we have to add a “finish” procedure that is deployed to close the trace file and starts nam.

proc finish {} {
global ns nf
$ns flush-trace
close $nf
exec nam out.nam &
exit 0
}

     Consequently, the simulator objects are used to execute the “finish” procedure after 5.0 seconds of simulation time and that is highlighted in the following command.

$ns at 5.0 "finish"

          To this end, we say that we have full focus on Tcl files in Ns2. As well as, we support you in developing your own ideas in this research area. Our research professionals assist you to acquire the best results through the utilization of all the required information. Be in touch with us for various research assistances.