1 Reply Latest reply on Aug 9, 2018 1:14 AM by deniszinchenko

    CYW943907AEVAL1F Netx_Duo UDP Broadcast

    deniszinchenko

      Hi.

      I have a program, which stream video over AP by (RTP+RTSP).

      I have periodical task with frequency 40ms and it send about 9-10 packets  with size 1300 per task execution.

      All fine with unicast address eg. host have 192.168.10.1 and receiver 192.168.10.2.

       

      But when I try to send UDP broadcast(192.168.10.255(mask 255.255.255.0) or WICED_IP_BROADCAST(255.255.255.255)) there is a lot of packets lost(up to 50%).

      I try to uncomment NX_DISABLE_UDP_INFO , increase WICED_DEFAULT_UDP_QUEUE_SIZE from 5 to 20, reduce WICED_ALLOCATE_PACKET_TIMEOUT from 2000 to 30, but nothing help. There is no error occurs at send and no packet creation fails. Also I`ve tried to use different type_of_service for UDP socket. There is any difference in implementation of unicast/broadcast UDP packet send? Or someone have idea how to increase efficiency of UDP video streaming?

      Thanks for answers!

        • 1. Re: CYW943907AEVAL1F Netx_Duo UDP Broadcast
          deniszinchenko

          I`ve made some tests.

          Seems WiFi physical interface guarantees delivery of the package for unicast IP, even it is UDP packet on protocol layer.

          I have 26 RTP-AP frame, which have about 15-17 separates packets. There is no packets lost, so video is fine, too.

          But, when I try to send for broadcast, I have loss rate about 3-12% depended on distance, etc , and if only 1 packet in a frame is lost - all frame lost too for decoder on receiver side. That`s why video have lags. Even with good quality WiFi 3%*15=45% packets lost.