Lexmark International, Inc.

International Business Machines Corporation

James Ronald Booth

Roger Steven Cannon

Bryan Scott Willett

Gary Allen Denton

Kelly Ann Killeen

James Paul Drummond

Keith Bryan Hardin

Adam Jude Ahne

Christopher Alan Adkins

John Thomas Fessler

Graydon Randall Dodson

Carl P Cole

James L Beck

Lynn M Oliver

Donald Reid Bush

Mike Partington

Matthew David Clarke

James Francis Webb

John Parker Richey

Martin Geoffrey Rivers

Daniel Eugene Pawley

James C Buchanan

Timothy J Louie

Lloyd Phillip Young

William Pohl Corbett, Jr

Charles S Aldrich

Stephen R Troyer

John Bruce Berry

Warren J Spina

Alan F Neel, Ii

Margaret E Claffey-Cohen

John Francis Gostomski

William M Schuller

James P, Ward

John Francis Gestomski

Joshua Scott Potter

Ellis Matthew King

A method of making a physical unclonable function (PUF) having magnetic and non-magnetic particles is disclosed. Measuring both magnetic field and image view makes the PUF difficult to counterfeit. PUF may be incorporated into a user-replaceable supply item for an imaging device. A PUF reader may be incorporated into an imaging device to read the PUF. Other methods are disclosed.

Methods of making physical unclonable functions having magnetic and non-magnetic particles

Methods for authenticating printer supply items using revocation lists are disclosed. Revocation lists are updated using DNSSEC to communicate between a printer and a DNS name server. A first domain name is created containing a request for a challenge to an authentication module and sent to the DNS name server. A second domain name is created containing a response to the challenge and sent to the DNS name server. The DNS name server indicates success or failure, which is used to authenticate the printer supply item. Other systems and methods are disclosed.

Systems and methods for authentication of printer supply items

A rotating magnetic physical unclonable function (PUF) is disclosed. Rotating the PUF enables robust low cost PUF readers. PUF may be incorporated into a user-replaceable supply item for an imaging device. A PUF reader may be incorporated into an imaging device to read the PUF. Other systems and methods are disclosed.

Rotating magnetic measurements of physical unclonable functions

A physical unclonable function (PUF) imaged through two faces is disclosed. The PUF is difficult to counterfeit because the view through both faces must be duplicated for a successful counterfeit. PUF may be incorporated into a user-replaceable supply item for an imaging device. A PUF reader may be incorporated into an imaging device to read the PUF. Other systems and methods are disclosed.

Physical unclonable function imaged through two faces

Systems and methods for authenticating printer supply items using revocation lists are disclosed. Revocation lists are updated using DNSSEC to communicate between a printer and a DNS name server. A domain name is created containing a printer supply item serial number, a message digest, and a message authentication code. The domain name is sent to the DNS name server, and the returned IP address is used to update a revocation list. Other systems and methods are disclosed.

A memory module, including a plurality of memory cells and a plurality of signal lines for communicating with a processing device. The memory module is configured such that following reception of a command and upon encountering a first condition while processing the command, the memory module limits a voltage on a first signal line of the plurality of signal lines to be no more than an intermediate voltage greater than voltage levels corresponding to a binary zero state and less than voltage levels corresponding to a binary one state for a period of time for indicating an occurrence of the first condition.

Addressing, command protocol, and electrical interface for non-volatile memories utilized in recording usage counts

A physical unclonable function (PUF) having magnetic and non-magnetic particles is disclosed. Measuring both magnetic field and image view makes the PUF difficult to counterfeit. PUF may be incorporated into a user-replaceable supply item for an imaging device. A PUF reader may be incorporated into an imaging device to read the PUF. Other systems are disclosed.

Physical unclonable functions having magnetic and non-magnetic particles

Electrical interfaces, addressing schemes, and command protocols allow for communications with memory modules in computing devices such as imaging and printing devices. Memory modules may be assigned an address through a set of discrete voltages. One, multiple, or all of the memory modules may be addressed with a single command, which may be an increment counter command, a write command, a punch out bit field, or a cryptographic command. The commands may be transmitted using a broadcast scheme or a split transaction scheme. The status of the memory modules may be determined by sampling a single signal that may be at a low, high, or intermediate voltage level.

A method of operating a module is disclosed. The method includes determining if a voltage between a power connection and a ground connection exceeds a predetermined threshold and if so determined then setting a module communication address to a first address, responding to a first serial communication received via the serial communication connection addressed to the module communication address, and not responding to a second serial communication received via the serial communication connection addressed to a different address than the module communication address. Other methods and devices are disclosed.

Methods and apparatus for setting the address of a module using a voltage

A method of operating a module is disclosed. The method includes determining a voltage between an I2C clock connection and a ground connection, setting a module communication address based on the determined voltage, receiving via the I2C clock connection and the I2C data connection a first command addressed to the module communication address, and responding to the first command. Other methods and devices are disclosed.

Methods and apparatus for setting the address of a module using a clock

An imaging device scan unit, including an oscillator oscillating in a predetermined oscillation pattern; a light source generating a light beam for deflection by the oscillator and including a forward sweep portion when the oscillator moves in a first direction of the oscillation pattern and a reverse sweep portion when the oscillator moves in a second direction different from the first direction thereof; and components defining at least two optical paths for the light beam, the forward sweep portion of the light beam passes through a first optical path and the reverse sweep portion of the light beam passes through a second optical path, the second optical path reverses a sweep direction of the reverse sweep portion of the light beam such that the forward sweep portion and the reverse sweep portion of the light beam are in the substantially same direction when exiting the scan unit.

Scan unit for an imaging device and methods of using same

Addressing, command protocol, and electrical interface for non-volatile memories utilized in recording usage counts sensor

Methods for authenticating firmware in a computing device include partitioning functions critical to the intended role of the computing device so that, upon successful authentication of the firmware, all functions of the device are made operational. Otherwise, the computing device behaves in a diagnostic mode of operation to assist users in troubleshooting to eventually authenticate firmware. At least first and second sets of firmware are loaded at various times into a controller of the computing device with the first set occurring without verification of trustworthiness, while the second set occurs upon authentication of the first. The second is used to authenticate a remainder set of firmware. Particular computing devices contemplate laser printers, mobile phones, PDA's, gaming consoles, etc. Firmware downloads, error messaging, hash comparisons, signature table construction, page-in techniques, computer program products, and particular computing arrangements are other noteworthy features, to name a few.

Dual boot strategy to authenticate firmware in a computing device

Growing community of inventors

Nicholasville, KY, United States of America

James Ronald Booth