Security Key Interface for JTAG Port Protection

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing electronics protection methods, such as debug or test ports, can be exploited for reverse engineering, potentially compromising national or economic security by allowing unauthorized access to proprietary designs, especially in advanced military or commercial applications.

Innovation Solution

A system and method that utilize a security device with a test access port and security key port, where only authorized access is enabled by a valid security key, intercepting and controlling the test-mode-select input to prevent unauthorized access to protected devices.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If a test access port is provided for debugging and testing purposes, then ease of operation is improved, but security is worsened due to potential reverse engineering

Engineering Contradiction:

Improvedebugging and testing accessVSAvoidreverse engineering risk

Core Design Contradiction:

Ease of operationVSObject-affected harmful factors

Solution Approach 1:

A security device is introduced as an intermediary component between the test access port and the protected device. This security device includes a security key interface that must be properly authenticated before allowing any test access signals to reach the protected device, thereby mediating the interaction and preventing unauthorized access while maintaining legitimate debugging capabilities

Inventive Principle:

Principle #24Intermediary (Mediator)

2Productivity

If standard test access protocols (IEEE 1149.1 JTAG) are implemented, then productivity is improved through standardized testing, but reliability is worsened due to vulnerability to exploitation

Engineering Contradiction:

Improvetesting efficiencyVSAvoidsecurity against exploitation

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The security device performs preliminary authentication actions by requiring a valid security key to be inserted and verified before the test access port can function. This preliminary security check ensures that only authorized testing can proceed, preventing exploitation while maintaining standardized testing protocols for authorized users

Inventive Principle:

Principle #10Preliminary action

3Ease of manufacture

If test access is made widely available for integration purposes, then ease of manufacture is improved, but loss of information is worsened through potential proprietary data exposure

Engineering Contradiction:

Improvesystem integration capabilityVSAvoidproprietary design exposure

Core Design Contradiction:

Ease of manufactureVSLoss of information

Solution Approach 1:

The security device acts as a mediator that controls the flow of information between the test access port and the protected device. It allows necessary test and integration signals to pass through while blocking or encrypting any attempts to extract proprietary information, thus facilitating manufacturing and integration without compromising intellectual property

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS7844997B2Securing standard test access port with an independent security key interface

Publication Date: 2010.11.30 HONEYWELL INTERNATIONAL INC

AI summary

A system to prevent unauthorized access to a protected device includes a test access port operable to mate with a test access connector, a security key port operable to mate with a security key and a security device in electrical communication with the test access port and the security key port. The protected device is in electrical communication with the test access port when the security device is enabled based on the security key. The test equipment is authorized for access to the protected device when the security device is enabled.