Why do I get this “Limited Connection” message?

I think it means that the relay server is being used. If so, this doesn’t make sense. The two devices are in the same room and are plugged into the same router. What can I do to tell these devices that they are on the same network?
The server IP Address: 10.0.0.11 (Named “NASPLEX” in the message.)
The player IP Address: 10.0.0.23
The router IP Address: 10.0.0.1