somewhat as an aside ... the requirement(s) given the X9A10 financial standards working group for the development of the X9.59 standard was
* to preserve the integrity of the financial infrastructure for all retial electronic payments without the use of encryption "ALL" didn't just mean internet or just mean credit .... it met "ALL" ... all environments ... all types of transactions, etc. "Without the use of encryption" didn't mean that information hiding wasn't precluded (say for privacy reasons) but weren't required to preserve the integrity of the financial infrastructure (aka that complete clear-text could be made available and it wasn't possible to do a fraudulent transaction based on everybody in the world potentially having the cleartext of that payment transaction). Implied in the requirement was that it had to also be extremely lightweight in order to be applicable to some of the existing electronic payments environments. Again "ALL" met "ALL" ... including a large number of existing electronic environments. Frequently "from scratch" protocol definitions are faster to do if you don't have to take into account any existing infrastructure (and/or only addressing an extremely small subset of the total end-to-end problem).. To meet the requirements we eventually settled on a very lightweight, end-to-end authentication definition (strong authentication of every transaction had to flow completely through from the consumer all the way through to the consumer's financial infrastructure). x9.59 references: http://www.garlic.com/~lynn/index.html#x959 [EMAIL PROTECTED] on 12/31/2001 8:32 pm wrote: to which I would add: 3. Cryptography, and therefore PKI, is meaningless unless you first define a threat model. In all the messages with this Subject, I've only see one person even mention "threat model". Think about the varying threat models, and the type of cryptography one would propose to address them. Even the most common instance of encryption, encrypted web forms for hiding credit card numbers, suffers from addressing a limited threat model. There's a hell of a lot of known plaintext there. --------------------------------------------------------------------- The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to [EMAIL PROTECTED]