How does all this work? The RMS station you reached connects via the Internet to a common message server (CMS), one of five mirror servers scattered on the Internet in strategic locations around the world. CMS servers deal with the requests and outgoing messages, collect any messages addressed to you, and then send them back to the RMS stations. RMS stations then transmit them to your boat’s mobile radio station. Propagation conditions (sun spots, solar flares and the like), as well as the quality of your radio installation, affect the speed of these exchanges between the boat’s SSB radio and the RMS station. Four thousand miles is probably a practical distance limit for good transmissions, though on good nights it can go up to 6,000 miles. At high latitudes, say north of the Arctic Circle, it might be harder to connect quickly; patience and perseverance become great virtues. Also, very active Northern Lights displays will kill SSB communications for short periods.