Here's an interesting link to play with: http://developer.talentsoft.com/examples/validate/validate.wml Basically, they're running a simple "mod-10" check. If you put in a fake credit card number, it will know it's fake. If you put in a valid number, it will confirm its validity. Of course, you would want to check that with a card that expired already (or, even better, a canceled card) since that page isn't secure, plus who the heck is "Talentsoft" anyway? Regardless, the expired or canceled card will come up as having had a valid number because every credit card number has a mathematical algorithm that dictates several parameters of the number. (I don't know what that is, but here's an example: The first and third numbers added together, divided by the last number, might equal a number that equals the 12th number when its digits are added together -- that kind of thing.) Doc P.S. There is something even more startling on their site -- an anonymous email sender. Here's the link for that: http://developer.talentsoft.com/cgi-bin/webplus.cgi?Script=/examples/webmail/index.wml
I've got a small program that does that. Mine actually goes out and dings up the issuer of the card and checks their data base to see if it's a valid card or not. Actually dials the phone if the computer is not already on the internet.
Gee, Bill, that's really state-of-the-art technology you have there! : ) Pretty much what they've done since the 60's! SK
Not sure why you or anyone would want to check the MOD10 of an expired or cancelled card...but: WARNING, do not ues a real credit card #!!, many scams use those kinds of sites to collect valid CC#'s from unsuspecting people. I am not saying that this site is unreputable, but why put a CC# into a slot on the web that will return valid or invalid when you know it is valid....just to get a response that says "Thank You"? -Peace, Dave
When i was a hacker like 15 years ago i made a program that would take a "seed" card and generate new ones by sequencing the # and then recalculating the mod-10... lol made me think back to my early teen years..
