Bug 2929

Summary: Prevent IdealWifiManager from adding incompatible modes in IEEE 802.11ac
Product: ns-3 Reporter: Varun Reddy <varunamarreddy>
Component: wifiAssignee: sebastien.deronne
Status: RESOLVED FIXED    
Severity: normal CC: ns-bugs, tomh
Priority: P3    
Version: ns-3-dev   
Hardware: All   
OS: All   
Attachments: Patch
Test Case

Description Varun Reddy 2018-06-16 02:11:16 UTC
Created attachment 3112 [details]
Patch

WifiMode throws an error message when a mode is used with incompatible channel widths or spatial streams. For instance, when channel 36 (20 MHz channel) is used with ideal wifi manager, the following message is thrown:

assert failed. cond="IsAllowed (channelWidth, nss)", msg="VHT MCS 9 forbidden at 20 MHz when NSS is 1", file=../src/wifi/model/wifi-mode.cc, line=214

However, the user has no control over which MCSs are added to Ideal Wifi Manager, despite knowing that MCS 9 is incompatible when Channel 36. This patch simply prevents IdealWifiManager from adding incompatible modes.
Comment 1 sebastien.deronne 2018-06-18 05:57:00 UTC
Varun, do you have any test case to reproduce the assert?
Comment 2 Varun Reddy 2018-06-18 10:00:21 UTC
Created attachment 3113 [details]
Test Case

The test case is a modified version of examples/wireless/wifi-tcp.cc
IdealWifiManager is used with channel number 36, which is a 20 MHz channel.
Comment 3 sebastien.deronne 2020-04-18 09:37:59 UTC
This bug can be closed, in the meantime there is a check in Ideal whether a mode is valid or not, and if not is getting skipped.