* Dave Emery: > Correct me if I am wrong, but don't most of the passive, cheap > RF or magnetic field powered RFIDs transmit maybe 128 bits of payload, > not thousands and thousands of bits which would be enough to include > addresses, names, useful biometric data and so forth ?
Those that perform actual cryptographic operations can store tens of thousands of bits. Even older tags (without proper crypto) easily reach 2**15 bits. These tags (for example, MIFARE) are usually not considered RFID tags by privacy activists, even though they can be read at some distance (but not with COTS equipment). Contactless readers are only used for user comfort (you can leave the card in your purse) and to counter vandalism, not for tracking purposes. The tags you are referring to are RFID tags used in logistics which usually provide only very, very few bits (which sometimes can't even be changed). --------------------------------------------------------------------- The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to [EMAIL PROTECTED]