Hi Rob! :-)

 RS> In other words, the likely-hood of 2 different MSG-IDs producing the 
 RS> same CRC is reduced when using longer MSG-IDs with more 
 RS> unique-to-that-message data.
Correct. However, this still bears the possibility of false positives, i.e.
messages considered to be dupes although they had different MSGIDs. The
probability can be kept low by chosing an appropriate algorithm, but it's
still not 100% safe. Only storing and comparing the full MSGID text is
safe.

Ciao
Pascal

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