Even after the authentication servers shut down pirates will be able to play the game with no issues.

Just tell the customer how to program them so that the programming can be done 'close' to the authentication server.

"We have an authentication server that tracks usage," he said.

It handles passing the login and encryption credentials to the authentication server.

I operate under the assumption that any online authentication servers will be shut down before I can install the game.

It's not like they're using some third-party authentication server.

The same process repeated on the authentication server will yield the same result if the correct secret was used.

The security of authentication servers is often neglected.

The token and the authentication server must have synchronized clocks.

To do this some sort of synchronization must exist between the client's token and the authentication server.