Administrative Regulations on Radio Waves Article 32

Identification signal shall be a call sign, maritime mobile service identity or other recognizable identification methods.Maritime mobile service identity (MMSI), which is a series of digits designed for maritime mobile services and maritime mobile-satellite services as prescribed in ITU Radio Regulations, is sent to uniquely identify ship stations, ship earth stations, coast stations, coast earth stations or other stations.The recognizable identification methods provided in Paragraph 1 may be one or more of the following: station name, station location, operation agency, official registration mark, the flight identification number, selective calling number or signal, the selective calling identification number or signal, the characteristic signals, the characteristic of the emission or other clearly distinguishing features readily recognized internationally.