Actually, sending the three bits of data plus the PIN does not generate any extra security. Unless all this info is encrypted when sent, anyone listening in can capture the info and impersonate your users.

Furthermore, you are using "security through obfuscation". By not publishing your pin-generation code / algorithm, you hope that no-one who somehow finds the three bits of data will be able to "guess" the pin-code. 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.

Actually, a secure link plus a user-id and password is sufficiently secure for most applications. The password is never stored on your system (so nobody can compromise the passwords even if they hack your database), just the result of a one-way trapdoor function (which is a function which has no inverse, so you cannot calculate the password from the result, other than by brute force).

CountZero

A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

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

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