wi-fi p2p peers discovery downgrades wlan bandwidth

Question

When I initiate wi-fi peers discovery by p2p_find command in wpa_cli (wlan is the only interface) network bandwidth sugnifically slows. Tried it on Android Lollipop and Kali Linux, both are affected.

Thanks airmon-ng and wireshark, I see not too intensive flow of probe frames, about one frame in 3 seconds. Seems not too much, but it slows bandwidth up to twice, even more sometime!

(To monitor bandwidth I use excellent speedometer tool on Kali, and custom application on Android).

Why p2p discovery does have so much effect?

Answer 1

Radio scanning requires the wireless adapter to temporarily switch to different frequencies in order to find peers (or APs) across all available channels. This means that it cannot communicate with your main network due to being on the wrong frequency.

(To avoid breaking the connection completely, the adapter rapidly jumps between scanning a random channel and transferring queued data on the regular channel.)