Secure Communication Key Validation Method

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current secure communication systems for mobile and portable radios face challenges in interoperability and security when encryption keys are provisioned differently among communication units, leading to potential eavesdropping and spoofing attacks.

Innovation Solution

A method that allows communication units to securely communicate by validating encryption keys based on unit identification codes, where the receiving unit compares the encryption key used by the transmitting unit to its own associated key and optionally to the key associated with the transmitting unit, preventing unauthorized access and ensuring secure processing of transmissions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the receiving communication unit validates the transmission using a particular group of keys provisioned in the receiving communication unit, then the validation process is simplified and faster, but transmissions from communication units using keys outside the searched set are rejected, reducing interoperability

Engineering Contradiction:
Improvevalidation process simplicityVSAvoidinteroperability
Core Design Contradiction:
Ease of operationVSAdaptability or versatility

Solution Approach 1:

The receiving communication unit performs preliminary actions by maintaining multiple sets of encryption keys (first set for its own unit identification code, second set for transmitting communication unit's identification code) before validation is needed. This preliminary preparation enables the unit to validate transmissions from different sources without requiring real-time key exchange or complex runtime decisions, thus maintaining both simplicity and interoperability

Inventive Principle:
Principle #10Preliminary action

2Adaptability or versatility

If the receiving communication unit validates the transmission against all encryption keys with which it has been provisioned, then interoperability with different key configurations is improved, but the system becomes vulnerable to spoofing attacks by unauthorized communication units

Engineering Contradiction:
ImproveinteroperabilityVSAvoidsecurity against spoofing
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The validation process applies different quality standards to different key sets. The first set of encryption keys (associated with the receiving communication unit's own unit identification code) is treated with higher trust authority than the second set (associated with transmitting communication unit's identification code). This local differentiation in validation strictness allows the system to maintain interoperability through multiple key sets while preventing spoofing by requiring the transmitting unit's key to be properly authorized in the receiving unit's first set

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP2253096B1Method to allow secure communications among communication units
Publication Date: 2019.09.25 MOTOROLA SOLUTIONS INC
  • EP2253096B1 patent drawingFigure 1
  • EP2253096B1 patent drawingFigure 2

AI summary

A first communication unit receives an encrypted transmission from a second communication unit. The encrypted transmission was encrypted by the second communication unit using a first encryption key. The first communication unit compares the first encryption key to an encryption key associated with the first communication unit. If the first encryption key matches the encryption key associated with the first communication unit, the first communication unit processes the encrypted transmission further. If the first encryption key does not match the encryption key associated with the first communication unit, the first communication unit compares the first encryption key to an encryption key associated with the second communication unit. If the first encryption key matches the encryption key associated with the second communication unit, the first communication unit processes the encrypted transmission further; otherwise, the first communication unit does not process the encrypted transmission further.