Hole punching (UDP) last step not working

Hi,

Im trying to establish direct connection between two computers on the internet, i’ve read that i need to create what is called hole punching , here is what i have achieved successfully

  • create a server on the internet ,
  • establish connection between the server and the two computers,
  • collect computers public ip/port
  • send computer A public ip/port to computer B (TCP)
  • send computer B public ip/port to computer A (TCP)
  • send some data (UDP) from computer A to B or B to A using the public ip/ ports (not successful, nothing shows up on both consoles after sending)

any ideas why the last step is not successful

Thanx

i tried doing all data transfer protocol in UDP but it did not work, i did the same by doing everything in TCP too with no luck
any idea why i can’t connect two clients that have each other public IP/Port,
please help thax