Question about Wifi Mac Retransmit Time in v3.35

[Shu Lan]

I want to modify wifi mac retransmission times in ns3 (3.35).

I know that seems to be related to Slrc and Ssrc in RemoteStationManager.

I use examples/wireless/wifi-tcp.cc as a demo.

After making as a few modifications (increasing the distance between Ap and Sta node to 130 etc.) as possible, I don't see Slrc or Ssrc property in the config file.

I can not observe changes in throughput by modifying the parameter value of slrc or ssrc.

Here is the config file lines:

And here is the code.

Thanks for all replies.

[Soulimane Mammar]

Hi,

Ssrc and Slrc have to do with the number of retransmission attempts !! I guess this is not what you want to modify.

Perhaps you have to dig in the ns3::FrameExchangeManager class

Regards

[Shu Lan]

I do want to modify the number of wifi mac retransmissions attempts. But it does not work.
The config file does not include slrc or ssrc property of remote station manager. 

This is the reason for this picture.

[Soulimane Mammar]

Hi,

Have you tried using:

Config::Set ("/NodeList/[i]/DeviceList/[i]/$ns3::WifiNetDevice/RemoteStationManager/MaxSsrc", UintegerValue(V) );

where [i] is the node you want to configure and V the value of MaxSsrc

Regards

[Shu Lan]

Yes,I tried it.

As an example:

    uint32_t retrans = 3; 

  Config::Set("/NodeList/0/DeviceList/0/$ns3::WifiNetDevice/RemoteStationManager/MaxSsrc",UintegerValue (retrans));
  Config::Set("/NodeList/1/DeviceList/0/$ns3::WifiNetDevice/RemoteStationManager/MaxSsrc",UintegerValue (retrans));
Perhaps you can download and run the above code wifi-tcp.cc to see if the config file contains these two properties in your ns3 environment.

Maybe the location of this code is wrong?

[Soulimane Mammar]

Hi, 

I took a look to the source code of ns3::WifiRemoteStationManager and it looks like that MaxSsrc and  MaxSlrc  not gettable and that explains why you couldn't find them in the config file.

After Modifying wifi-remote-station-manager.cc and wifi-remote-station-manager.h the problem is solved

Find attached your file with some added code (just for testing) and the modification of  wifi-remote-station-manager.cc and wifi-remote-station-manager.h

Regards

[Shu Lan]

First, thank you very much for your help!

I think this is the correct way to solve it.

But the code you provided may not match the version 3.35.

Could you please provide me your ns3 version number？

So that I can check what has been modified accordingly.

Best wishes

[Soulimane Mammar]

Hi,

I'm using 3.33. I did just a couple of modification 

Find attached the diff so you can do the changes yourself

Regards

[Shu Lan]

Hi, it works correctly!

Thank you. I appreciate your help.