[adjuvantjfoster]

http://www.navcen.uscg.gov/marcomms/gmdss/dsc.htm has, way down in the document, a lot of useful stuff of interest to those struggling with what would be useful in MacENC:

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The new Universal Shipborne Automatic Identification System will be backwards compatible to DSC, allowing countries having GMDSS A1 areas to establish AIS operating frequencies, and additionally identify and track vessels equipped with AIS. More importantly the same nine digit identity (MMSI) used in DSC for calling is used by the AIS in identifying vessels.
Classes of Digital Selective Calling

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