Army of Two uses a deterministic (peer to peer) approach for networking versus a traditional client-server approach.  We do this so we can have all the synchronized animation gameplay that exist in the game.

This solution is solid for our game but also exposes us to risk in terms of lag, if we're not careful. In a peer to peer connection the person with the worst connection brings down the whole group to his/her worst connection level.

While not generally a problem for COOP (since most people play co-op with friends) when playing in Versus mode 3 people can be highly adversely affected by one player with a bad connection. We use the region lock to minimize the likelihood of this occurring.