Dubai new behaviour
 

Hi,
I'm testing now the voxalot service in Dubai and here are my new findings wrt the old ones.
Conditions :
1- ATA 2100
2- Port tested 5060 and 80
3- ISP : Du
4- One side is in Dubai the other in Egypt

Status:
1- The registration is always OK, and dial tone is heard. (I assume ports are open then)
2- The first call initiated by any side works perfect and the call is fine.
3- Just after this successful calls (one initiated from each side), all attempts lead to one symptom : one way audio, Egypt can hear dubai but Dubai can not.
4- The symptoms are very consistent, after 12 hours the whole cycle repeated again, 2 calls went fine originated from both side.
Then one way audio again !!!!

Conclusion:
1- Port are not blocked as registration is working fine and dial tone is here all the time.
2- I guess a self intelligence somewhere understands the SIP packets (RDP) and kills them.
3- After a certain timer (few hours) this killing rule is reset!!!

Can you help me with suggestions to try to make it happen please?
Thanks for your great help

i heard that all voip is blocked in UAE, maybe this is the cause, but i heard that only bestip devices are working fine