Simulating large file transfers take time due to the initial fragmentation of the entire file. NetSim GUI limits the maximum file size to 1GB. However, you can set larger file sizes, if you are running via CLI mode or using the multi-parameter sweeper. 

Let us consider an example where you wish to send a 1GB file across the network. Further let us assume you send one such file every 16s, which translates to an application load of 500 Mbps ((1 * 10^9)* 8)/16). Two options that you can consider to reduce simulation time are: 
  • Generate 500Mbps traffic load using CBR; the settings would be
  • Reduce the file size and IAT. For example, generating 500 MB files every 16s is the same as generating 250 MB files every 8s or 125MB files every 4s or 62.5 MB files every 2s

2. Make sure plots, packet trace and event trace are disabled


3. Whether you are using FTP or CBR you can run for the minimum necessary simulation time.
  • If you are using UDP then since there is no temporal variation (after the initial transients) even 5s of simulation would give you an accurate answer.
  • If you are using TCP, and if there is no path loss in the wireless link, again there would be no variation with time. Hence the results with one file transfer itself would be accurate.