Comment Mod up the "FUD" factor of the headline (Score 2, Informative) 180
Its really no big deal. The vast majority of RFID chips are simply read-only, because thats the bottom of the line cheapest way to go. The card is "pinged" with a radio-field, and the chip burps out its serial number. No over write. No virus attack potential. Nothing of interest... Sure you can spoof these by putting a different tag in its place - oh yay, you've done the same cleverness as peeling a price sticker from a different product.
Read/Write tags are a step up in cost. They range from 20 bytes to 256 bytes of data with a 10 digit serial number. Some brands support encrypted encoding formats. There is a trivial one byte "access key code" that prevents a Writer from writing to an RFID tag if this "access key code" byte doesnt match. Its really more of an accident prevention mechanisim (so you dont accidentally overwrite an ExxonSpeedPass if it was put in a WalMart system).
Encryption of the "Writable" tags is the responsibility of the application. Since you only have 20 bytes (on the more common, cheaper tags) there isnt much you can do anyway as the number of permutations at 20! is low enough for most script-kiddies to crack. When you start getting upto 256 bytes, then sure it makes absolute sense to encrypt the contents. But, when you're at that price level, you're already considering the hardware that can encrypt at the signal level.
(Yes, I write code dealing with RFID tags)
-Mike
Read/Write tags are a step up in cost. They range from 20 bytes to 256 bytes of data with a 10 digit serial number. Some brands support encrypted encoding formats. There is a trivial one byte "access key code" that prevents a Writer from writing to an RFID tag if this "access key code" byte doesnt match. Its really more of an accident prevention mechanisim (so you dont accidentally overwrite an ExxonSpeedPass if it was put in a WalMart system).
Encryption of the "Writable" tags is the responsibility of the application. Since you only have 20 bytes (on the more common, cheaper tags) there isnt much you can do anyway as the number of permutations at 20! is low enough for most script-kiddies to crack. When you start getting upto 256 bytes, then sure it makes absolute sense to encrypt the contents. But, when you're at that price level, you're already considering the hardware that can encrypt at the signal level.
(Yes, I write code dealing with RFID tags)
-Mike
