encryption

I need to encrypt credit card number in a MS-SQL 7.0 database field that is called ... cc_number. I can purchase a com object if it is not too expensive. The only thing is that usually you have to provide the key or a password to encrypt and decrypt in the asp code so it is not very safe if a hacker has access to your asp pages. I would like you embed the key or password in a dll with the option to modify this key or password from an html page. Also I saw that the component vendors propose several encryption method (MD5, RC4, RSA,...), any idea if one is really superior to the others? Just to sumarize: The encryption and decryption part is easy since with the right component it should be just one line of code. What I really need is to combine this encryption, decryption thing with another dll where the password or key is located. Instead of haveing decript(...,...,"password",...) I would have decript(...,...,variable,...) where you get the data from the dll. It should be possible too to change is from an html asp page. I hope my explanations were clear. Email me if you have more questions. ## Deliverables Complete and fully-functional working program(s) in executable form as well as complete source code of all work done. Complete copyrights to all work purchased. ## Platform win 2000 IIS5.0 ASP MS-SQL server