Modern passports are more than just bits of cardboard. The microchip inside the back cover stores an encrypted copy of the user photo along with an X.509/PKI compliant certificate quite similar to the ones used on the web to make "padlock" secure websites work. The difference is that the certificate in the passport chip identifies a user rather than a site.
There is also an antenna which allows the chip data to be read from a range of a few inches away. There is no worry about someone sneaking up to your back pocket with a portable scanner though - you can only read the chip data once you have the key. How do you get the key? By opening the passport and optically scanning the page with lots of chevrons ">>>>>>>>>>>>>"
Modern passports are more than just bits of cardboard. The microchip inside the back cover stores an encrypted copy of the user photo along with an X.509/PKI compliant certificate quite similar to the ones used on the web to make "padlock" secure websites work. The difference is that the certificate in the passport chip identifies a user rather than a site.
There is also an antenna which allows the chip data to be read from a range of a few inches away. There is no worry about someone sneaking up to your back pocket with a portable scanner though - you can only read the chip data once you have the key. How do you get the key? By opening the passport and optically scanning the page with lots of chevrons ">>>>>>>>>>>>>"