Friendchips

“the AVID brand Friendchip type is peculiar due to its encryption characteristics. The simple fact that a cryptographic feature is provided in a chip would not necessarily be unwelcome; few pet rescuers or humane societies would object to a chip design that outputs an ID number “in the clear” for anyone to read, and, in addition, has authentication features for use by scanners that know how to use them, for detection of counterfeit chips. But the “Friendchips” have been found lacking in actual authentication features, and rather easy to counterfeit well enough to fool the AVID scanner. Although there’s no authentication encryption involved, there is obfuscation encryption, meaning decryption secrets are

needed, to convert what the chip transmits into its original label ID code.”

via Identification Systems: Microchipping Animals.

http://maxmicrochip.com/ – DIY scanner & code. Plus online decryption tool for Friendchips.

http://en.wikipedia.org/wiki/Microchip_implant_(animal)