This applies to lossy communication with or without feedback and with or without a server. Feedback is just another layer of confirmation messages. If the serv

This applies to lossy communication with or without feedback and with or without a server. Feedback is just another layer of confirmation messages. If the server is up and sends a confirmation message to one side, but the other side disconnects before receiving the confirmation message (or before sending the acknowledgement that it received the confirmation message), you have another Byzantine Generals problem. With a server, it's just a connection of 3 generals with the server in the middle, instead of a peer-to-peer connection.