9 Replies Latest reply on Sep 2, 2016 8:46 AM by Intel Corporation

    Wifi access point dropouts under wifi load

    Thors

      We are observing strange (and to us very problematic) wifi dropouts on Edison. I wonder if anybody else has seen these and knows of a possible solution or workaround.

       

      Use case

      The Edison's wifi is in access point mode, and we are continuously sending data (like ~1MB/s).

       

      Problem

      What we observe are sudden stalls in the transmitted data. During these stalls only the beacon frames are send. The Edison cannot be reached/pinged from any associated device.

      After some time (2..~60sec) the Edison starts sending data again.

       

      Observations

      The dropouts/stalls can be resolved by trying to associate another device to the access point (works also with incorrect password).

       

      It seems that how often it appears is related to wifi conditions and/or client types. With some clients it is more noticeable than with others. It can be reproduced very well with Ubuntu 14 using intel wifi card, but it also appears with certain Android and iOS devices.

      To reproduce we tested using vanilla Edison images with just access point enabled and generating traffic using netcat.

       

      We tried some things already, but they did't work:

      • Using different distributions: yocto 1.7.2 and 1.7.3, ubilinux (150309)
      • Updating hostapd to v2.5
      • Using different carrier board (Arduino, Mini, and our own custom board)
      • Using different antenna's (internal, several external types)
      • Try using a more recent driver for the chip. It seems Intel has made significant modifications to it, so that path was abandoned.

       

      Any help on this will be much appreciated.