VHF digital selective calling also has other capabilities beyond those required for the GMDSS.

In the U.S., MMSIs are primarily used for digital selective calling and for assigning Inmarsat identities.

An area within the radiotelephone coverage of at least one VHF coast station in which continuous digital selective calling (Ch.70/156.525 MHz) alerting and radiotelephony services are available.

This capability allows communications receivers effectively to monitor many channels at once, perhaps using digital selective calling (DSC) techniques to decide when to open an audio output channel and alert users to incoming communications.