
Based on the public outcry, the State Department made revisions to the
proposed system, including encrypting the data on the RFID tag and printing
the key on the optically read section of the reader for decoding on the PC.
This way, any intercepted data is garbled and unreadable without the key,
which is accessible only with physical access to the passport. It is hard to
imagine a 128-character key being printed on a passport, let alone strong
publicly vetted encryption being used on the tag. Presuming the encryption
method is known or learned, the key space for searching the information is
considerably small and within the realm of brute force attacks. ...