Contention Window Set up in NS3 WiFi Simulations

[Kamran Zia]

Hi 

Txop.cc module of NS3 takes in values of Cwmin and Cwmax as arguments and they can be set up using following lines of code:

Config::Set("/$ns3::NodeListPriv/NodeList/*/$ns3::Node/DeviceList/*/$ns3::WifiNetDevice/Mac/$ns3::RegularWifiMac/Txop/MinCw", UintegerValue(cwmin));
    Config::Set("/$ns3::NodeListPriv/NodeList/*/$ns3::Node/DeviceList/*/$ns3::WifiNetDevice/Mac/$ns3::RegularWifiMac/Txop/MaxCw", UintegerValue(cwmax));

Now the DCF function in set up in wifi-mac.cc module where there is function called "ConfigureDCF" that takes in cwmin and cwmax values. ConfigureDCF function is used in Regular-wifi-mac.cc module (line 1593 and line 1598) where it takes cwmin and cwmax values as input. Now these values are declared (kept fixed not variable) in regular-wifi-mac file as cwmin=15 and cwmax=1023 (line 1546 onwards) for different IEEE standards. 

My question is that whatever value i set up in the config::set command, the regular-wfi-mac and ConfigureDCF values will always use 15 and 1023 values for cwmin and cwmax respectively. So, how can I set up my own min and max values of CW in my NS3 simulations. 

If I am not understanding something correctly here, please guide me on this matter.

Hoping to hear from experienced NS3 community.