6112 is the network port.
Your ISP isn't going to help you with that because it isn't an ISP issue.
You need to set port forwarding through your router to forward ports 6112 - 6119 to your computers network IP address.
The game is not broken, this is how classic battlenet worked.
Back in the day it was common knowledge that if you wanted to play any of these games you needed to ensure your network was set approprietly. Modern games have automatic network detection and configuration.
lol the game is broken.....
Not exactly. When Diablo, Warcraft 2 Battle.net Edition, and Starcraft came out, they worked fine with no port configuration required. I played all these games on Windows 95 and 98 without having to do any of that.
What changed was security configurations over time. Some time in the 2000s (yeah a long time ago, but not back in the day of these games) the games started requiring port forwarding on more modern setups.
I wish GOG would do a bigger overhaul of these games so they could be enjoyed by more people that don't want waste their time with the extra steps, or just don't want to ruin their network security. Blizzard should get on it, and help them improve Battle.net. This game is a recent relaunch, and its already dead. Not a single person logged in as I type this.