Problems with wireless Multicast Stream in AV Installation

[Marco_Pfiffer]

Hi Community,
I have a problem running a AV streaming device in a customers wireless network. The device is the following: https://www.wolfvision.com/vsolution/index.php/en/presentation-systems/cynap/overview
The network setup is as follows:
2 pcs. Summit X460-48p
6 pcs. AP3825i
1 pcs. V2110 Hyper-V Edition

Streaming through the wired network is no problem either multi- nor unicast has any issues. Streaming through the wireless network does only work with unicast streams. At the moment I activate the multicast group 225.0.0.1 I get a very bad picture and a very slow connection speed to the wireless network. It makes no difference if I use a laptop, iPhone or iPad (Airplay works fine). I have activated multicast bridging for the VNS and added 0.0.0.0/0 All Multicast.

Within the wireless network I have 25 participans 80% smart devices 20% laptops so this should be no problem for the above mentioned network setup.

I have read through the articels about multicasting and I can´t find a way to get it work.

By the way, connecting the wolfvision device to a standalone AP with 811.2n everything works fine. So for me it looks like I have screwed up something with the multicast handling.

Thanks for your help!

Marco

[Ostrovsky__Yury]

Hi Marco. First of all, make sure you set DTIM to 1, since multicast packet will be sent every DTIM period. Second - multicast by default using Minimum basic rate , so try to increase it up to 24 Mbps. Thats the first step. There are also some multicast optimization settings, but that you can dtart playing with after you fix first two things I mentioned. Btw, what is the video stream bitrate you using?

[Jarek]

Hello All,

I'm not a big fan of multicast stream via wireless, but...
Marco you wrote that you have a group 225.0.0.1.

As we know (or nor not  ) multicast has address overlap 32:1.
In this case we have group 225.0.0.1 and this is the same as 224.0.0.1.

Old school says that we should avoid class 224.0.0.0/24,
(address like X.0.0.Y and X.128.0.Y,)
because this is groups are copied to CPU.

Maybe this is the issue ? Maybe stream is soft switched?

--
Jarek

[Ostrovsky__Yury]

I would also recommend to open a case with GTAC, include your configuration and the file sample . You can share the case # here, so probably we can ask our QA to run the file and see if there any problem .

[Ostrovsky__Yury]

Well, if you are not using mulicast-to-unicast conversion, there should be not match difference between the number of endpoints, the video stream should be only one, right? The end points are in the same subnet, on the same SSID? On your wired network, make sure you do not using any dynamic multicast routing (PIM,DVRP) between VLANS. The conversion will help when the number of clients is not high , becouse each packet goes with much higher speed then multicast -instead of MBR its using full data rate, but at the same time the number of packets multiplying to the number of clients.

[Marco_Pfiffer]

Hi Yury, I have tried your solutions and it improved the streams. I also played around with the mutlicast optimization settings you and Ron mentioned but I still get no satisfying stream especially when I try to stream to two or more endpoints on the same AP.