But really it would not take a genius to guess the "join + MD5 or CRC hash" method. So don't rely on such amateurish security.

That's why one of the joined fields should be some secret value. The key/password, so to speak. It should never be an issue whether the algorithm is public or not. Only the key needs to be private.

But you do have a point. If the user already has a key/password, why would he need a PIN too? It's just another password. Two passwords are not more secure than one.

In reply to Re^2: Need a wait to generate a 4 digit "PIN" number by ikegami
in thread Need a wait to generate a 4 digit "PIN" number by jaiello

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