ISDN Call Error "Data Corruption" and "Re-Estlablishing"

[mail2vkc]

HI

We are using TANDBERG 6000 and have ISDN Pri connected to it. When we make ISDN call to BRI Number within Telecom Service Provider Network,It work Fine. But when International call goes out of ISDN PRI Telecom Servcie provider the ISDN call is Unstable. I frequently get error " DATA Corruption " and Video goes Blanks with No audio. Call doesn't get disconencted but a message " Re-Establaishing call... Pls Wait " occurs for about 2 Min and then the call resumes.
When Checked with Servcie Provides he see no error on his network.

Is there any way to solve this ISDN error over International call

[Joe Vallender]

Chances your call is not being sent over clear channel trunks or trunks that are not data capable (ie, voice trunk(s) with echo cancellers). You should open a ticket with your local ISDN provider to trap and trace your call to ensure the path. They may need to open a ticket with the LD provider they are handing the call off to, to trace the LD/INTL portion.

[Entropy3XD]

Try setting your Tandberg to 56k instead of 64k. I have seen this problem before when going across trunks. Sometimes telco will throw your call over to a restricted 56k channel and you typically get loss of video and data corruption.

[Entropy3XD]

Addition:

There is no dynamic routing of H.320 calls. This means you are stuck if telco throws you over to a restricted channel (56k channel). To fix, have the dialing codec dial with bonded 56k channels instead of 64k channels. If you can dial with 64k channels and it connects with good video, yet the video goes bad after awhile, you should turn off "fall back to telephony".

Symptoms for hitting a restricted channel include:
1. Tiling that fills in very slowly
2. Frozen video
3. No video even though multiple channels are connected
4. Call connects, then drops
5. Any of the above with audio that is howling or a digital "chirp"