A self-authenticating device and a method for authenticating the self-authenticating device may be provided.

A self-authenticating printed document (101) comprises text and a symbol (102) printed on the document (101).

Then, authentication of the self-authentication-type two-dimensional code is performed by determining whether or not the decoded bit sequence md matches a bit sequence m included in the RS bit sequence.

The SWAT transparently performs self-authentication of data written to the data storage disc and reports information characterizing failed read commands.

The transparent field acts as a self authentication device.