Audio but no Video

[Terytee]

I (commerical company) recently had to connect an ISDN call to an Air Force site. I'm using ISDN, he was using IP, but dialed through a bridge on the base that routes call out.

We connected at 384, but had no video, just audio. Tried several attempts with the same results; audio, but no video.

Cameras are all working fine and I can connect to any other site inside my company's network using ISDN. Of course the Air Force tech is blaming my equipment.

I suspect that its some sort of network imcompatibility, but is this resolvable??

[Unclefester]

I had almost the same issue today. Two of my sites (Cleveland & Arlington, VA) tried connecting to a MGC-100 in Vermont. We dialed out at 384 and only connected at 64K. Tried H.261, H.263 & H.264 we had video once but it came in and out. We are using TB MXP880's. We tried for about an hour and no avail.

[Slimey]

Have them check access-lists on routers or firewalls that may be blocking some ports.

[fatron]

I've encountered this problem when trying to connect my old polycom 512 via Ip to a newer Polycom bridge. I think Polycom did some modifications that make it so the new equipment doesn't always like the older stuff. Also, like said above, have them check their firewalls and ports. I have one 512 in my posession that just won't work behind a firewall. All of my units have the same software version, and are configured the same, yet one of them won't receive video when it is behind the firewall. Very strange.

[helix-2000]

Might want to also check to see if AF endpoint using some sort of crypto device.

[DRI]

What type of ISDN Gateway is the USAF using?

[11B-33T]

If they had audio then it wasn't a crypto issue folks.

Sounds like the MCU/bridge built & launched the call; AF H.323 site IP'ed into the call hosted by the MCU; commercial H.320 site dialed into call using number supplied by bridge; calls completed and audio but no video was negotiated.

Many questions to be asked before fingers can be pointed. You connect fine within your own company net but can you talk with any other ISDN sites on the outside? What type of codecs were being used? Was the MCU set for auto transcoding or hardset? Just a couple of of starting points...

[Unclefester]

I had almost the same issue today. Two of my sites (Cleveland & Arlington, VA) tried connecting to a MGC-100 in Vermont. We dialed out at 384 and only connected at 64K. Tried H.261, H.263 & H.264 we had video once but it came in and out. We are using TB MXP880's. We tried for about an hour and no avail.

I had a call with this bridge again today. We had to drop the call to 128 but it connected with no issues. He is using a bridge that his company built. I can't remember the companies name. We found out the site we were trying bridge to was dialing them ISDN. So the little devil in me said screw the bridge and dialed direct. Call lasted 6 hours no problems. Tells me might be a bridge problem. :silly:

[Burt.Kloppers]

Hi,

I have found that with the newer VC systems with H.239 enabled on the systems and going through certain firewalls without a firewall transversal video does not connect on one side or both but audio always connects.