I Trying to implement the UDP Hole Punching. I have a server program which running on Static IP address and port. Client A(behind the NAT and firewall where UDP traffic is allowed) Client B(data card)
Client A is running behind NAT (Cisco) and other Client B is running through data card (Reliance India).
Both Client A and Client B is using the Tcp connection to connect with the Server and getting the public IP and port of each other.
When i start the hole punching process Client B which running on data card able to receive the Hole punch request (data) from client A but Client A (behind the NAT) is not able to receive the Hole Punch Request from Client B.
I tested Client A with Win Stun it is showing "NAT With Independent Mapping and Independent Filter"-voip will work with Stun. does not preserver the port number does not supports hairpin of media.