note 43277 added to function.srand

From: Date: Wed, 16 Jun 2004 14:59:59 +0000
Subject: note 43277 added to function.srand
Groups: php.notes 
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office's comment about multiplying by 1234567 instead of 1000000 is slightly misguided for a couple of reasons. first, as the editor note would indicate, 1234567 is not a prime number. second, the problem he is attempting to fix is that the random values are slowly converging. this, however, is not a problem with the seeding of the random number generator, but a problem with the RNG itself. most default RNGs that come with programming languages will converge because they were written for efficiency and to function in everyday programs. if you need a Pseudo Random Number Generator (PRNG) that is cryptographically secure and does not converge after repeated use without seeding... you will unfortunately have to use a different generator. There are several out there such as the MersenneTwister, Yarrow (by Bruce Schneierer of Counterpane Security) and more being made every day. Due to the hassle of finding a reputable PRNG, it is recommended that you only need to use those for issues that require strong security such as gambling games and cryptography. hope this cleared things up :) ---- Manual Page -- http://www.php.net/manual/en/function.srand.php Edit -- http://master.php.net/manage/user-notes.php?action=edit+43277 Delete -- http://master.php.net/manage/user-notes.php?action=delete+43277&report=yes Reject -- http://master.php.net/manage/user-notes.php?action=reject+43277&report=yes Search -- http://master.php.net/manage/user-notes.php

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