How does the Online Session system determine what is a valid session and what isn't?

We’re having trouble getting connection to work between Android and PC devices. Until recently, the system has worked just fine, so we know that the interconnectivity between platforms works.

The problem is that the Android devices cannot see a session hosted on the PC, and vice-versa. Recently we branched our build in Perforce, pushed all changes to the Android branch and built the Android version from there. The game now seems to think that building it from a different locations makes it a different game entirely.

If this isn’t the case, what does the Engine do to figure out whether it can join a session or not? We don’t see Unreal Tournament sessions in the Multi-player Shooter example, so how does the Engine distinguish between games?

Did you ever manage to sort this out? I can host and join my game on my PC through LAN, but when launching my game on Android it doesn’t find any sessions.

Edit: I got Android and PC to work by using ClientTravel and port forwarding 7777 udp. The host must also use the listen command.