Your method is not 'totally secure' because you have to store the nonce in a database. If you generate a SID from an MD5 digest based on user authentication information, this hash does not have to be stored. It can be generated when the cookie is inspected.

Also if you run a large site with millions of users, your source of entropy can be depleated quickly, negating any security you would have gained.

In reply to Re: Re: Re: Using MD5 and the theory behind it by rpc
in thread Using MD5 and the theory behind it by r.joseph

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