note 39622 added to function.uniqid

From: Date: Wed, 04 Feb 2004 23:39:02 +0000
Subject: note 39622 added to function.uniqid
Groups: php.notes 
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the idea that two strings out of 50,000 could evaluate to the same md5 hash is quite impossible. there are 2^128 MD5 values. an interesting proof showed that given 10^19 inputs there would still be less than a 50% probability of a duplicate hash. assuming you had a computer that could process md5 hashes in 1 ms it would take 10^19ms (370,000 years) of hashing to have less than 50% chance of finding a duplicate. if you really did find two strings that have the same md5 hash you will be quite famous. see http://www.cs.bham.ac.uk/~mdr/teaching/modules/security/hash.html for the proof.</p> ---- Manual Page -- http://www.php.net/manual/en/function.uniqid.php Edit -- http://master.php.net/manage/user-notes.php?action=edit+39622 Delete -- http://master.php.net/manage/user-notes.php?action=delete+39622&report=yes Reject -- http://master.php.net/manage/user-notes.php?action=reject+39622&report=yes Search -- http://master.php.net/manage/user-notes.php

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