Wowza Community

Bosch IP camera multicast

We’re trying a new h.264 IP camera from Bosch, the Dinion NBN-921-P. Since we need to have a bunch of users connect to both the camera (hyper low-latency) and Wowza we want to multicast the traffic from the camera. Awesome. Set up multicast and have it working great in VLC. No matter how many people connect the CPU stays around 20%.

Using the same URI: rtsp://IP/?multicast=1 in Wowza yields a very high CPU marker. Opening Wireshark shows that the multicast stream is not flowing to Wowza but instead it is Unicast.

Was wondering if anyone knew how to force this to be multicast. I don’t have an SDP file from the camera. When I do multicast the camera and pcap it, then set an expression of ‘sdp’ in Wireshark I don’t get any results so I’m not sure how to manually build the file either.

Anyone have any clever options? Any way to force Wowza to try and grab the multicast? Any way to easily get the SDP information downloaded from the camera either via a pcap or some other clever method?

As always, thanks for your help!


If you turn on debug logging in VLC and connect to the camera over RTSP you can capture the SDP data from the VLC logs. Save this as an SDP file in Wowza Server content folder. That should be it.


You should see and RTSP DESCRIBE request from VLC. It is the response from the describe that includes the SDP data. I might try this:

  • Launch VLC with -vvv option

  • Open View: Add Interface: Debug Logging

  • Open Media: Open Network Stream

    You should see the RTSP exchange in the debug window with the SDP data response to the DESCRIBE request.


Maybe I’m crazy, but I try: vlc -vvv “rtsp://IP/?multicast=1”

And that outputs a verbose log but no SDP. I also tried ‘Video -> Add Interface -> Debug Logging’ but got the same.

Is this a Linux only thing maybe? I feel like I’m missing something simple here.