My choice of code for this is:

$session = substr(crypt(rand(),'XX'),2);

Which creates a tidy 13 character (printable) string with no fuss or muss. The session is used to create a MySQL table entry (where the session field is a unique primary key). There's a loop to keep generating session ids if the row insert fails due to a duplicate key. I could throw a time element into it, but I don't think this would buy any improvement.

I suppose there are also ways to defeat the not so random nature of 'rand()', but I'll leave that to the DOD ;).

Assuming a 13 char string is sufficient variation to (reasonably) prevent a session attack.

In reply to Re^6: Identifying clients by ruzam
in thread Identifying clients by ruzam

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