1. Randomly Generate Tokens
According to many security experts, the only way to guarantee that tokens are not able to be reversed is if they are generated randomly."If the output is not generated by a mathematical function applied to the input, it cannot be reversed to regenerate the original PAN data," Adrian Lane, analyst for Securosis, recently on the topic. "The only way to discover PAN data from a real token is a (reverse) lookup in the token server database. Random tokens are simple to generate, and the size and data type constraints are trivial. This should be the default, as most firms should neither need or want PAN data retrievable from the token."
The link for this article located at H Security is no longer available.