No Video on Polycom m100 software through MCU 4515 sw 4.5(1.45)

[Rachael Mast]

Hi Everyone!

I have a dilemma, and I know the answer is going to be "Polycom m100 software is not compatible with Cisco MCU 4515," but that's not a good answer for the guys I work with.  So, my problem is, when a customer with Polycom m100 software dials into my MCU 4515 Software version 4.5 (1.45), they receive no video.  I was able to troubleshoot the problem down to the MCU's H.264 codec.  Apparently Polycom and Cisco don't get along when it comes to the H.264 codec and everyone has their own standard.  (Love it!).  So, if I uncheck the H.264 on my MCU, ta-da! Polycom m100 software gets video... but!  New problem - We also have customers that use CUCI Lync (Cisco Unified Communications Integration with Microsoft Lync).  If H.264 is turned off on the MCU, my CUCI Lync friends don't get video.

I'm at a loss.  Is there any way to make both of them happy?

[Rachael Mast · Accepted solution]

Cisco's Response:

1.            As you probably already know, Polycomm M100 nor CMA/RealPresence Desktop is not supported by the MCU. I know that Polycom has put a EOL on the M100s, so most likely they will not make any changes to the M100s.

2.            According to the BU, the MCU is operating to specification, but Polycom has many limitations with the Codian MCU.

                1.            More specifically, when you upgraded from 4.4 to 4.5, there were some new H.264 parameters added.  Those parameters is likely due to Polycom’s M100 not being able to cope with the added H.264 parameters.

                                1.            Here is a sample SDP parameter line for H.264 main video.

                                                1.            a=fmtp:126 profile-level-id=42e014;packetization-mode=1;max-mbps=27600;max-fs=3600;max-fps=3000;max-smbps=79000;max-dpb=1380;max-rcmd-nalu-size=196608

                                                2.            Max-fps (max frame rate), max-dpb (max decoding picture buffer size), max-rcmd-malu-size (max recommend NAL-unity size) are new in the 4.5.

                                2.            You cannot control the parameters on the MCU, but you can insert a SIP Proxy in the middle of the signaling path to rewrite all the parameters. However, Cisco does not support this.

                                3.            Even though this issue is prevalent for SIP, I can most likely guarantee that there is a comparable change for H323.

                2.            To reinforce that Polycom knows about this, here are some of the Polycom bugs found in their release notes (http://downloads.polycom.com/video/m100/RelNotes_1_0_7.pdf):

                                1.            Interoperability: Codian MCU

                                                CMAD-2272

                                                When placing a SIP call from the Polycom Telepresence m100 to Codian MCU, you get a blank screen on Telepresence m100.

3.            The BU’s recommendation is to disable H.264 for only those Polycom M100s by using the preconfigured endpoint feature on the MCU, setting a custom codec to exclude H.264. Polycom M100 seems to work well with H.263 video. Their other recommendation is to move away from the M100s only because Polycom nor Cisco’s BU will try to support this.

[Martin Koch]

Thank you for answering your question yourself.

I would also have recommended to try the pre configured participants, but that will not scale if you have many of them.

You did not mention your deployment, if its a VCS you should be able to force calls,

for example to a specific number (with or without rewrite) to a specific protocol or neighbor zone

which could force the call to h323, which sounds like an option as well.

Maybe some CPL could also do some tricks here.

I could picture with opensips a free sip proxy you could do some rewrites of the sdp,

but as cisco said, thats nothing they support.

To look a some other MCU or softclient can also be an answer.

Did you try if the m100 towards TPS behaves different?

How did you fix the issue in your deployment?

[Rachael Mast]

Hey Martin,

The issue exists with H323 and SIP.  A lot of my customers dial to my MCU via IP address then enter the conference ID, so usually, the MCU see's their specific IP address as my VCS IP.  I tried to set preconfigured participants that come in with the VCS's IP to the H263 codec, which works, but I still have other customers that may come in that way that still need to use the H264 codec.  For now, the answer is to keep the MCU at 4.4 unless we absolutely need to upgrade.

Polycom M100 software isn't the only Polycom software that isn't supported by the Cisco MCU, it's also their newer software types like RealPresence Desktop and CMA Desktop.  I'm slowly trying to convince my customers to stop using Polycom, but they requested some kind of replacement that works just like it, and I haven't found anything yet that you don't need to connect to a server.  My customers prefer to have something they can install and go.  Polycom m100 gives that to them, so they're pretty upset that it has to go away.