Authentication using magnetic field based on current drawn by security device

Abstract

Systems and methods for determining authenticity of a security device of a component in an imaging device includes receiving, by the security device, an authentication challenge including one or more commands and executing, by the security device, the one or more commands in response to receiving the authentication challenge. A magnetic field profile is generated based on current drawn by the security device from a power source while the security device is executing the one or more commands, the generated magnetic field profile indicating an authentication response of the security device to the authentication challenge for use in determining authenticity of the security device.

1 . An imaging system, comprising:
 an imaging device having
 a power source, and 
 a controller with a first security device chip; and 
   a supply item having
 a housing, and 
 a second security device chip connected to the housing, the second security device chip for receiving an authentication challenge from the first security device chip including one or more commands when the housing of the supply item is installed in the imaging device, wherein when the second security device chip receives the authentication challenge the second security device chip is operative to execute the one or more commands while drawing current from the power source of the imaging device such that a magnetic field is generated around a conductor carrying the current drawn by the second security device chip while executing the one or more commands, the generated magnetic field indicating an authentication response of the second security device chip to the authentication challenge. 
   
     
     
         2 . The imaging system of  claim 1 , wherein the controller determines authenticity of the supply item by comparing the generated magnetic field with an expected magnetic field profile. 
     
     
         3 . The imaging system of  claim 2 , wherein the expected magnetic field profile is predetermined. 
     
     
         4 . The imaging system of  claim 2 , wherein the expected magnetic field profile corresponds to a second authentication response to the authentication challenge of a third security device chip on another supply item having another housing installed in the imaging device. 
     
     
         5 . The imaging system of  claim 1 , wherein the second security device chip is operative to receive an authentication command to generate a second authentication challenge for sending to a third security device chip on another supply item having another housing installed in the imaging device. 
     
     
         6 . The imaging system of  claim 1 , wherein the second security device chip is operative to transmit a profile of the generated magnetic field as a magnetic field profile response to the controller when connected thereto for use by the controller in determining authenticity of the supply item. 
     
     
         7 . The imaging system of  claim 1 , wherein the second security device chip is operative to transmit a profile of the generated magnetic field as an expected magnetic field profile response for a third security device chip on another supply item having another housing installed in the imaging device. 
     
     
         8 . The imaging system of  claim 1 , wherein either the imaging device or the supply item further includes a magnetometer for measuring the magnetic field. 
     
     
         9 . The imaging system of  claim 1 , wherein either the imaging device or the supply item further includes the conductor. 
     
     
         10 . The imaging system of  claim 1 , wherein the power source is a voltage regulator. 
     
     
         11 . The imaging system of  claim 10 , wherein the voltage regulator draws power over a power bus from a power supply unit. 
     
     
         12 . The imaging system of  claim 1 , wherein the supply item is a toner cartridge and the housing contains toner. 
     
     
         13 . An imaging system, comprising:
 an imaging device having
 a power source, and 
 a controller with a system-on-chip with available memory and a first security device chip, wherein the power source delivers power to the first security device chip over a conductor, 
 the imaging device further including a magnetometer configured for measuring a magnetic field in the conductor upon current from the power source flowing therethrough; and 
   a supply item having
 a housing, and 
 a second security device chip connected to the housing, the second security device chip for receiving an authentication challenge from the first security device chip including one or more commands when the housing of the supply item is installed in the imaging device, wherein when the second security device chip receives the authentication challenge the second security device chip is operative to execute the one or more commands while drawing current from the power source of the imaging device such that said magnetic field is generated around the conductor and is measurable by the magnetometer. 
   
     
     
         14 . The imaging system of  claim 13 , wherein the magnetometer is configured to supply the magnetic field to the system-on-chip for storage in the available memory. 
     
     
         15 . The imaging system of  claim 14 , wherein the controller is configured to compare the magnetic field to an expected magnetic field profile also stored in the available memory to determine authenticity of the supply item. 
     
     
         16 . The imaging system of  claim 13 , wherein the magnetometer includes both hall effect and magnetoresistance technology. 
     
     
         17 . The imaging system of  claim 16 , wherein the magnetometer is configured to measure the magnetic field during a measurement duration started by a trigger condition of the controller. 
     
     
         18 . An imaging system, comprising:
 an imaging device having
 a power source, and 
 a controller with a first security device chip; 
   a first toner cartridge having
 a housing containing toner, and 
 a second security device chip connected to the housing; and 
   a second toner cartridge having
 a second housing containing second toner, and 
 a third security device chip connected to the second housing, 
   
       wherein both the second and third security device chips are configured for receiving an authentication challenge from the first security device chip and wherein during use the second and third security device chips draw current through a conductor thereby generating magnetic fields and the generated magnetic fields indicate an authentication response of the second and third security device chips to the authentication challenge. 
     
     
         19 . The imaging system of  claim 18 , wherein the authentication response may be supplied to any of the first, second or third security device chips. 
     
     
         20 . The imaging device system of  claim 18 , further including a magnetometer on either of the imaging device or the first or second toner cartridges configured for measuring the generated magnetic fields.