Computing device limiting mechanism

• US 7,669,048 B2
• Filed: 08/31/2006
• Issued: 02/23/2010
• Est. Priority Date: 12/09/2005
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Westerinen, William J., Xu, Zhangwei, Frank, Alexander, Steeb, Curt A.
• Primary Examiner(s): Lee; Thomas
• Assistant Examiner(s): Abbaszadeh; Jaweed A
• Application Number:
  US11/515,410
• Publication Number:
  US 20070136570A1
• Time in Patent Office: 1,272 Days
• Field of Search: 713/1, 713/2, 713/100, 705/52, 705/61, 705/77, 705/400, 705/418, 709/208
• US Class Current: 713/2
• CPC Class Codes: G06F 21/572 Secure firmware programming, e.g. of basic input output system [BIOS]
• CPC Class Codes: G06F 21/575 Secure boot
• CPC Class Codes: G06F 2221/2105 Dual mode as a secondary aspect
• CPC Class Codes: G06Q 20/085 involving remote charge determination or related payment systems
• CPC Class Codes: G06Q 30/0283 Price estimation or determination
• CPC Class Codes: G06Q 30/0284 Time or distance, e.g. usage of parking meters or taximeters

Abstract

Described is a technology by which a computing device is booted into a normal mode of operation or a limited mode of operation, depending on whether the computing device was operating correctly (e.g., with respect to policy) prior to a reboot. The reboot may be forced. Examples of incorrect state include an overdue payment on a leased computer, or improper execution of certain important software. A metering mechanism evaluates the state of the computing device, and when an incorrect state is detected, configures the computing device for operation in the limited mode, by setting the computing device to boot via one boot path (e.g., a limited-mode BIOS) instead of another boot path (e.g., a normal-mode BIOS). A BIOS selector switches to the limited BIOS on the next reboot, wherein the computing device is restricted to the limited mode of operation (regardless of subsequent reboots) until the correct state is restored.

Claims

1. In a computing device, a method comprising:

establishing a policy defining payment requirements for pay-per-use operation of the computing device;

collecting policy data related to the policy;

detecting that the policy data indicates the computing device is not compliant with policy defining payment requirements;

rebooting the computing device into a limited mode of operation supporting only networking, keyboard/mouse, display and, a provisioning packet download application;

connecting to a provisioning datacenter;

downloading a provisioning packet from the provisioning datacenter, the provisioning packet representing payment related to pay-per-use operation for re-enabling normal operation of the computing device; and

restricting the computing device to remain in the limited mode of operation until the computing device is compliant with the policy.

2. The method of claim 1 wherein rebooting the computing device into the limited mode of operation comprises booting the computing device from a boot path corresponding to the limited mode of operation instead of a boot path corresponding to a normal mode of operation.

3. The method of claim 2 wherein booting the computing device from a boot path corresponding to the limited mode of operation comprises:

providing a secure execution environment including a BIOS selector that selects between a normal mode of operation BIOS and a limited mode of operation BIOS, the secure execution environment further providing secured access to the limited mode of operation BIOS; and

setting the BIOS selector to boot the computing device from the limited mode of operation BIOS.

4. In a computing device, a system comprising:

a metering mechanism that observes a state of the computing device after booting with a normal-function BIOS and operation of a full-function operating system with respect to compliance with subscription terms for pay-per-use operation of the computing device, wherein the metering mechanism saves state data about operating mode through a reboot of the computing device;

a secure storage for storing a limited operating mode BIOS that, when active, limits operation of the computing device to an update-only mode of operation bypassing use of the normal-function BIOS; and

a selector coupled to the metering mechanism to operate the computing device using the normal-function BIOS when the metering mechanism indicates the computing device was operating in a normal operation mode prior to reboot, or to operate the computing device using the limited operating mode BIOS when the metering mechanism indicates that the computing device was operating in a limited operating mode prior to reboot.

5. The system of claim 4 wherein the selector and the metering mechanism are incorporated into an application-specific integrated circuit.

6. The system of claim 5 wherein the application-specific integrated circuit is incorporated into a multiple-chip module, and wherein the multiple-chip module further includes at least one component that contains the normal-function BIOS and the limited operating mode BIOS.

7. The system of claim 4 wherein the metering mechanism, the selector, and the limited operating mode BIOS contained in a secure execution environment incorporated at least in part in a CPU of the computing device.

8. The system of claim 4 wherein the computing device comprises a personal computer, and wherein the metering mechanism, the selector, and the second set of instructions are contained in a secure execution environment incorporated in a Southbridge chip of the personal computer.

9. The system of claim 4 wherein the limited operating mode BIOS causes a memory controller to configure less system memory than is configured for the full operating mode, wherein the lesser amount of system memory supports operation of an application program used to restore compliance with subscription terms for pay-per-use operation of the computing device.

10. The system of claim 9 wherein the limited mode of operation is capable of executing logic to restore the state of the computer to use the normal-function BIOS to allow full-function operation, including the first boot path instructions.