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What happens when your generated number matches an existing number? Is there a finite amount of possible CC numbers?
by maresca 12y ago
What happens when your generated number matches an existing number? Is there a finite amount of possible CC numbers?
- rtkwe 12y agoDo you mean a non Final number? That shouldn't happen since ever issuer is uniquely identified by the first 6 numbers on the card. For collisions with Final numbers they'll have to keep track of the numbers they've issued and if they have expired or not. Aren't online transactions validated with a combination of CC# and other details. They could use that to deepen their pool of numbers. They can also get multiple issuer numbers (the first 6 digits) giving them more numbers as well. Also temporary card numbers aren't completely new so they're probably drawing on existing solutions to collision issues.