An authentication method for authenticating an article in a device
includes the steps of (a) reading an identification number stored on the
article, (b) reading an authentication number stored on the article, (c)
determining an input number based at least in part on the identification
number, (d) applying an authentication function to the input number to
calculate an output number, (e) determining that the article is authentic
only if the authentication number corresponds to the output number, and
(f) permitting use of the article in the device if the article is
authentic, and disabling use of the article in the device if the article
is not authentic.