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Video streaming over WiFi

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I'm trying to stream video using RTP over DDS connected via WiFi. This works great for a single subscriber, but breaks when two people try to watch the stream.

When there are multiple subscribers, OpenSplice switches to multicast. As explained on wikipedia, mulitcast over WiFi causes more packet loss and a lower datarate.

What would be the best way to allow multiple subscribers to work properly?

I tried to set AllowMulticast to false, but this caused the entire node to not be discoverable. I assume this is because it uses multicast for discovery? I have not yet found how to disable it for data only.

[edit] AllowMulticast changed from a boolean to a list of values, setting it to spdp allows sending data as unicast. The question that remains is if multicast can be used effectively over WiFi

I also tried to connect the subscribers over wired LAN, hoping that there would be less conflicts in the multicast traffic. But even though IGMP snooping is enabled, the video is still broadcast over WiFi. I assume because the publisher is subscribed to the multicast group that it writes to. Is there a way to set up multicast such that traffic is not re-broabcast on the WiFi interface?

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Hi Pepijn,

First of all, apologies for the reaction-time, our domain was hijacked and we had to re-establish the forum on this new domain: forums.opensplicedds.orgĀ 

We have seen several usecases where WiFi is successfully used (even with broadcast) yet no doubt that its 'sensitive' and might induce a lot of re-transmissions in case you require reliable transfers. Often periodic transfers don't require a reliable transport but that depends on the usecase.

You might throttle the bandwidth in your DDSI setup (see deployment manual on how to configure that) to prevent 'bursts' ..

We do have solutions to use broadcast on the LAN and then have gateways that transparently 'tunnel' that traffic from 1 LAN to another (and/or from a LAN to a CLOUD) over a (potentially entrypted) TCP-link .. and then re-multicast that again at the destination .. not sure if that would address your usecase though ..

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