Simulation Procedure 

Introduction 

Design of the scenarios is explained in the previous chapter and the actual simulation process followed is explained in this chapter. Step by step process followed to create the required scenarios is explained in this chapter and simulation steps to create the network, nodes, server, application config, mobile config, profile config and DES metrics used to estimate the performance are also explained in this chapter along with the corresponding screenshots. As explained there are two scenarios used in this application and the detailed simulation process followed to create these two scenarios and also process followed to check the results achieved and simulation setup details are also explained in this chapter. 

Simulation process of first scenario 

As discussed in the previous chapter the basic design followed to create this scenario is MANETs and the mobile nodes are used as the required sensor nodes.  Wireless LAN server is used to act as the sink node and in this process 15 mobile nodes are used as the sensor nodes and the process to set to basic network is explained as below. The complete simulation process involves many steps and the detailed simulation process followed to create this complete setup is explained as below 

Simulation process of basic network 

Mobile ad hoc networks are used as the basic network in this simulation process and the actual process followed to create the basic network is explained in this section. A new project is created and it is renamed as per the user requirements and a blank scenario is created in this process. Following steps and screenshots gives the detailed description of the simulation process followed in this context 

  • OPNET modeler is started and a new project is selected from the file menu
  • Project name is given and also the scenario name is also given as per the user choice
  • Create blank scenarios is used as the option to create the scenario
  • MANET is used as the required network and it is selected at the node family options level
  • Every network should be created at a certain location and in this simulation process campus is chosen as the required network location
  • Size of the network is set to 1000 X 1000 square meters and thus a new network scale is created in this context and thus the required basic network is ready now 

When the basic network is created, an object palette is created and opened at the user interface level and now the simulation can be done by simple drag and drop operations from the object palette. Below screenshot shows the basic MANET object palette used in this simulation process and the also the actual objects used in this scenario creation process

From the above object palette it can be observed that there are different types of nodes available across MANET simulation process and among these nodes, the actual nodes used across this simulation and network creation process are as listed below 

  • One wireless LAN server fixed node is used and this behaves like the sink node and controls the senor nodes
  • 15 wireless LAN mobile nodes are used and they act as the required sensor nodes
  • Required applications are created using the application configuration node
  • Profile definitions are created using the profile configuration node
  • Mobility to all the sensor nodes is given by the mobile configuration node

Above mentioned nodes are created on the empty scenario space using the object palette and a simple drag-drop operation would help in creating the basic network. Below screenshot shows the basic network setup of this scenario and it contains all the all the nodes as mentioned above

From the above screenshot it can be viewed that all the required nodes are created and shown in the workspace and once these nodes are added to the basic network setup they need to be configured to set the simulation process and the actual procedure implemented in this context is explained in the coming sections.

Application definitions process 

The simulation steps followed to create the basic network is explained in the previous section and now this section deals with the configuration process of the application definitions. From the design chapter it is clear that application configuration node is used to define the required applications and in this simulation process a single application is used to generate the required traffic. As discussed file transfer application is used to create and generate the TCP traffic and the actual process followed in this context to create the FTP application for the application configuration is given in the form of the below steps 

  • Application configuration nodes is selected and a simple right click will open the option called edit attributes
  • Now chose this option to edit the required attributes and a separate window is opened in this context
  • Required attributes are edited now to add the application and the actual procedure implemented in this process is given below along with the respective screenshots

Above screenshot demonstrate the actual process followed to edit the attributes of the application configuration node. Application definitions section is elaborated and the number of rows is added against the number of applications and in this simulation process only one application is created and thus only one row is added to the number of rows column.  When the number of rows is added as one a separate section is opened and there the required application name is entered and in this scenario it is FTP.  Once the application name is added, the corresponding description of the application is also added where the FTP is chosen from the list of applications shown to the users and as shown in the above screen. Initially the FTP is set to off and now it should be expanded to activate the application and it can be observed that there are different types of FTP loads and for this simulation process a medium load FTP application is chosen as shown in the above screenshot. A medium load FTP application will generate the required TCP traffic across the network and also initiates the energy consumption aspects and once these settings are done to the application config node, Ok button is used to apply these changes. When the application definition settings are ready they should be applied to the profile definitions as well and the simulation process implemented in this context is as explained below 

Profile definition process 

Profile definitions are important to support the required TCP traffic generate by the FTP application that was created at the application configuration process and as explained in the previous section. Profile configuration node is used to set these profile definitions and the steps followed to create the required profile is given below 

  • Profile configuration node is selected and simple right click on the node will show the edit attributes option
  • Chose the edit attributes option and when done a separate window is opened at the user interface and now the required attributes are edited to support the application and also to create the required profile definition and shown in the below screen 

Profile configuration definition is shown in the above screenshot and from this screen it is clear that one row is created at the number of rows section. The number of rows is set to one as there is only one application available and that was created at the application config level and so a single profile is required to support the application created. Name of the profile is set in this process and it is set to FTP as the application created is FTP and now the description of the profile is also set in this process. FTP is chosen as the application to be supported against this profile and the number of rows used is one even in this process as there is only application to be supported for this single profile. There are few other options available to be set against the profile definitions and they are also done as shown in the above screen and the start time offset is set to a constant value of 10 seconds, where the duration of the profile is set till the end of the profile as shown above. Once all the required settings are done against the profile configuration they are applied across the network by clicking on the OK button as shown in the previous section. When the required application and profile definitions are created using this process they must be applied to the nodes and the wireless LAN server and the actual simulation process implemented at this level is explained in the below sections along with the corresponding screenshots. 

Configuration process for mobile nodes and wireless LAN server 

As mentioned in the previous sections a single wireless LAN server and 15 mobile nodes are used across the basic network setup and the configuration details and the corresponding simulation procedure are explained in this section. Routing protocol is required to support the generate traffic and initiate the routing operations across the network and in this simulation model, AODV is used as the routing protocol as discussed in the design chapter and the actual process followed to set this routing protocol is given in the below steps 

  • All the mobile nodes and the wireless LAN server are selected from the workspace
  • Now any one of the node is selected and right clicked such that to open the edit attributes option
  • When the users click on the edit attributes option a separate window for the selected node is opened and from here the required routing protocol can be chosen and the actual screen used in this process is as given below

AODV is selected as the required routing protocol to be supported by all the 15 mobile nodes and the single wireless LAN server and the corresponding process implemented is as shown in the above screen. From this screen it can be observed that there are different routing protocols available and from them AODV is selected and applied to all the selected objects by clicking on the Apply to selected objects option as shown in the above screen shot. Now the AODV routing protocol is applied to all the mobile nodes and also the wireless LAN server. Once the mobile nodes and the server are set to support the AODV routing protocol, each and every node on the network should be assigned an IP address and the actual process followed in this context is given below 

Process followed to assign IP address 

This section defines the process to be followed to assign the required IP address to all the nodes and the actual steps need to be followed in this context is given below 

  • Applications menu is visited on the OPNET tool and from there it can be observed that IP option is available
  • Now expand the IP option from where the users can identify few aspects while assigning the addresses to the mobile nodes and the wireless LAN server
  • Chose the option auto assign IP4 addresses to assign the corresponding IP addresses to all the nodes on the network and the corresponding screenshot is as given below

All the mobile nodes and the wireless LAN server are selected at the workspace and the applications menu is opened to view the above screenshot. From this screen it can be observed that IP protocol menu is opened and from there the addressing option is opened to assign the required address. From the above screen it is clear that Auto assign IPv4 addresses option is selected to assign the required IP addresses to the nodes and the wireless LAN server  and now the actual application settings need to be applied for all the mobile nodes and the server and the process implemented in this context is shown below 

Application settings for mobile nodes and wireless LAN server 

Once the basic network is ready to be simulated all the 15 mobile nodes and the single wireless LAN server should be set for supporting the corresponding application and profile configurations as set in the previous steps. This process can be done in either two different ways and they are as explained below with the corresponding step by step procedure 

  • All the mobile nodes are selected from the workspace and any one of the node is opened for editing the attributes and this can be done by a right click on the selected node
  • When the edit attributes option is selected a new window is opened to the users from where the application and profile settings can be done for the mobile nodes
  • Application destination preferences and the application supported profiles tabs are expanded to do the required configuration and the corresponding screens are as shown below 

From this screen it is observed that the application destination preferences tab is explored to set the required application and the number of rows is set as one as there is only one application created in this simulation process. The required application is selected and the corresponding symbolic server is also selected as FTP server as shown in the previous screenshot. Once the destination preferences are done now the actual application supported profiles option is used to support the FTP profile as created in the profile configuration time. Number of rows is set to 1 and FTP is selected as the required profile as shown in the previous screen and these settings are applied to all the selected objects by using the option apply to selected objects as shown in the above screen shot. Once the mobile nodes are ready to support the respective application and profile now the wireless LAN server is also set accordingly and the process is explained with the help of below steps 

  • Select the wireless LAN server and chose the option edit attributes to edit the required application and profile attributes
  • Now expand the option application supported services where a new window is opened to enter the profile to be supported
  • Add the number of rows to 1 as there is only one profile created in this scenario and the corresponding screen is shown in the below screen 

It can be observed from the above screen that a single row is created at the application supported services level and FTP is chosen the required profile to be supported and the corresponding description is set to support as shown in the above screen. Now click on the Ok button for two times to apply these settings to the wireless LAN server. As discussed previously there is another process to edit these attributes known as deploying the application and the below steps evaluate this process 

  • Open the applications menu available on the top of the OPNET workspace.
  • It can be observed that are different options at this level and now chose the option deploy the defined option and the respective screen is as shown below

Protocols menu is expanded and from here the application option is explored to do the deployment operation as shown in the above screen. From this screen it is clear that deploy defined applications option is chosen to deploy the network and the very next screen appeared to the users is as shown below 

The actual deployment process is shown in the above screen and from this screen it can be observed that all the mobile nodes are dragged towards the source and the wireless LAN server is dragged towards the destination. The consistency of the deployment process can also be checked with the button check consistency as shown in the above screen and with this all the mobile nodes and the server are ready to support the applications and the profiles created across the simulation process. Setting up the mobility to all the nodes is the last set of the total configuration and the corresponding process is as given below 

Process to define mobility 

As the sensor nodes are mobile in nature the required mobility should be set to the all the mobile nodes and this can be done with the help of the mobile configuration as discussed in the previous section. Mobility of the nodes can be defined at this level and the corresponding process implemented in this context is as given below 

  • Select the mobile config node and chose the edit attributes option by just a right click on the node
  • A new window is opened after this operation and the required mobility can be set and shown in the below screen 

From this screen it is observed there are three different options to choose the mobility to all the nodes and from this default random waypoint is chosen and the corresponding parameters are set in this context. Random waypoint parameters are set and the speed of the mobile nodes is set to 10 meters per sec and the pause time is set to 0 as shown in the above screen and from this screen it can also be observed that the start time is set to a constant value of constant 10 seconds and the stop time is till the end of the simulation. When the mobile config settings are done the same should be applied to all the mobile objects and the actual process followed in this context is as shown below

  • Open the topology menu and chose the option random mobility
  • There are various options available from this chose the option like set random mobility and the corresponding screenshot is as given below 

From the above screen it can be observed that set mobility profile is used to set the required mobility to all the mobile nodes on the network and this is browsed using the random mobility option and the actual mobility is to set all the mobile nodes on the network. Now the last step in the simulation of this scenario is to set the individual DES statistics and this process is as explained below 

Process to choose performance metrics 

 Performance metrics are required to understand the performance of the individual scenarios and also to compare the all the scenarios created in the simulation process and the actual process followed in this context is explained in this section.

  • Right click on the workspace of the network and from there chose the option to set the statistics
  • Choose individual DES statistics is clicked to choose the performance metrics and the corresponding screen is as shown below

Once this option is selected, a new window is opened from there the required options are selected against the performance analysis and the required screen is as shown below

From this screen it can be observed that there are three levels of performance metrics and from them Global statistics are used in this simulation process and the corresponding metrics used are as given below 

From this screen it can be observed that FTP application metrics are used and the actual metrics used to analyze the performance are as listed below 

  • Download response time
  • Traffic received in packets per sec
  • Traffic sent in packets per sec
  • Upload response time 

Now the wireless LAN metrics are used in this process and the corresponding screen is as shown below 

From the above screen it is clear that few wireless LAN parameters are also used and they are as listed below 

  • Data dropped
  • Delay in seconds
  • Load in bits per second
  • Medium access delay in seconds
  • Throughput in bits per sec 

Once all the required performance metrics are selected the simulation process of the first scenario is completed and the actual process to build the second scenario is as given below 

Simulation process of second scenario 

Simulation model of second scenario is almost same as the first one and the only process is at the wireless LAN MAC parameters and this scenario can be generated by just duplicating the first scenario from the scenarios option and the corresponding screen is as given below. Once the required scenario is duplicated now the required settings are changed for all the mobile nodes and the wireless LAN server and the corresponding screen is as shown below 

It can be observed that few settings are changed for the wireless LAN attributes from the above screen and the actual settings changed in this context are as given below 

  • Transmit power is set to 0.020
  • Packet reception power threshold is set to -95
  • RTS threshold is set to 256
  • Fragmentation threshold is set to 256
  • CTS to self option is set to enabled
  • Short retry limit is set to 7
  • Long retry limit is set to 4
  • AP Becon interval is set to 0.02 seconds
  • Max receive life time is set to 0.5
  • Buffer size is set to 256000
  • Roaming capability is set to disabled
  • Large packet processing is set to dropped

Now both the scenarios are ready and then the simulation is run for 5 minutes to achieve the results and the actual results obtained after the simulation run are explained in detailed in the next chapter.