Applicable VersionsNetSim AcademicNetSim Standard NetSim Pro  


Applicable Releasesv12v13/v13.1/v13.2


NetSim Supports different mobility models such as Random Walk, Random WayPoint, Group Mobility, File-Based Mobility, and SUMO-based model.


  • The Random Walk model is that of a random walk on a regular lattice, where at each step the walk jumps to another site according to some probability distribution.
  • The Random Way Point model is a commonly used synthetic model for mobility in Ad-Hoc networks. It is an elementary model that describes the movement pattern of independent nodes in simple terms. 
  • The group mobility model is a commonly used synthetic model for mobility in Ad Hoc networks. It is an elementary model that describes the behavior of mobile nodes as they move together.
  • In File-Based Mobility, users can write their own custom mobility models and define the movement of the mobile users.
  • In SUMO based model available in the VANET nodes, users can link the SUMO tool with NetSim to introduce vehicular movement in the nodes, with the help of a SUMO configuration file. 
  • The Pedestrian Mobility model is a commonly used synthetic model for mobility in Ad Hoc networks. It is an elementary model that describes the movement of nodes according to real geographic data such as buildings, streets, etc, and also destination-oriented movements such as dedicated start and endpoints.


Following screenshot shows the mobility models available in a sensor node:


Note that not all mobility models are available in all devices. There will be limitations based network being simulated 


Printing node position over time (possible only in NetSim Standard and NetSim Pro versions)

Open Mobility Project, and in Mobility.c and go to fn_NetSim_Mobility_Run() function. Inside the default, case add the following codes


fprintf(stderr,"\n The position of %s at time %.2lfms is X=%.2lf and Y = %.2lf \n",DEVICE_NAME(pstruEventDetails->nDeviceId),

pstruEventDetails->dEventTime,

DEVICE_POSITION(pstruEventDetails->nDeviceId)->X,

DEVICE_POSITION(pstruEventDetails->nDeviceId)->Y);

_getch();


Build Mobility project. Upon running a simulation involving mobile devices, users will see the node positions getting printed in the console during run time. The same can be obtained as a log by writing to a file instead of stderr. 


How do I set mobility using a MATLAB/Excel program


The simplest way to do this is to use a File-based approach; this approach does not require any modifications to NetSim code. Your program in MATLAB should write the device position with respect to time in a text file. The format is explained in https://tetcos.com/help/v13.2/Technology-Libraries/MANETs.html#file_based_mobility_model

In the devices which you wish to move per MATLAB data, set the mobility model to File-Based Mobility


The Open Mobility file option will open an empty mobility text file where you can provide your input generated from MATLAB in NetSim's mobility file format,



Note 
  • The mobility file is common for all devices in the network. Hence, if you want to introduce mobility in multiple nodes based on data from MATLAB all this information can be put together in the same mobility text file which NetSim will read at the simulation start.
  • NetSim does not check for errors in the mobility file. If there is a mistake the simulation will hang. Please cross your check your file prior to the simulation start

Related Articles:

  1. https://tetcos.freshdesk.com/solution/articles/14000084341-how-to-add-file-based-mobility-to-the-sensor-nodes-in-netsim-wsn-iot-
  2. https://tetcos.freshdesk.com/solution/articles/14000084737-how-to-convert-ns2-movements-file-to-netsim-mobility-file-format-
  3. https://tetcos.freshdesk.com/solution/articles/14000085541-how-to-perform-vehicular-network-simulations-using-netsim-lte-library-