Consulting for Dev of Audio Chat over IP using UDP Ports

Here is problem definition as you have requested.

We have developed peer to peer audio chat application for PC. It uses RTP protocol built over UDP.

We are using port range from 5000-6100.

Application works perfectly when two machines are in same LAN and also when two machines are directly connected to internet.

There is a problem which we are facing while working in following case:

When one machine is behind router and in LAN(Domain Controller) and when other machine is in other network and directly connected to internet. Then the machine which is in LAN and behind router not getting feeds of other machine. But other machine which is connected directly to internet is getting feeds of machine in LAN.

We need to understand and need help on the following

a.) How do we verify Which UDP ports have to be used ?

b.) Which UDP ports are not blocked by standard firewalls

We need some consultancy and guidance on the above. Knowledge of the above or experience of the above would help.

I guess around 4 hours of total consultancy over Skype / Telephony would be helpful.

Please quote Hourly rate.

.NET VoIP

Project ID: #687267

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