On Mon, 2009-11-09 at 12:39 +0100, John Black wrote:
> Ali Asghar Toraby Parizy wrote:
> > hi friends
> > I need a hash function to build a Unique serial number by mixing a request
> > code and a user name
> > request codes are strings like this: They are literally HEX codes of MAC mac
> > addresses.
> > "002314EFD000544AB05345300045675609782123C3254B312123D12312EE13123F123D123123E00000000E00000000E0000000E0000000E0000000E00000000E00000000"
> > i want to create a function that mix together this request code with user
> > name that user entered and create new serial number.
> > What implications i have to satisfy to create such hash function in php?
> > Thanks for any suggestion
> How about using sha1 to hash your string. If the data is unique then the
> hash will be unique as well.
> $string = $request_code.$user_name;
> $hash = sha1($string);
> Jeder hat soviel Recht, wie er Macht hat.
I'm not sure you can guarantee uniqueness, but you can say with a high
degree of certainty that it's extremely unlikely to not be unique!