Patent ID: 7529936

Claim:
A network including a sensing device for sensing coded data printed on a print media surface, a printer and a registration server, the network characterized by: a secret key and a first unique public identifier which uniquely identifies the sensing device being installed in a non-volatile memory of the sensing device and in a database of the registration server, before the sensing device is connected to the network via the printer; a second unique public identifier which uniquely identifies the printer being installed in the printer and in the database of the registration server; the printer configured to obtain the first unique public identifier from the sensing device and communicate to the registration server the first and second unique public identifiers; the registration server configured to determine from the received first and second unique public identifiers whether the sensing device should be registered with the printer and if so, to authenticate the sensing device by verifying an encryption from the sensing device, using the secret key, of a challenge message, the challenge message being generated, and transmitted to the sensing device, by the printer; upon successful authentication, the sensing device being registered in the database of the registration server so as to be associated with the printer; and, the sensing device, when placed in an operative position relative to the print media surface, configured to sense at least some of the printed coded data and, using the sensed coded data, generate indicating data indicative of the identity of the print media surface.