Self-Signed Implicit Certificates for Root CA Key Distribution

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional cryptographic systems face inefficiencies in bandwidth usage and operational transformations when generating and managing certificates, particularly for root Certification Authorities, as they require either large explicit certificates or complex implicit certificate schemes that lack complete authentication verification.

Innovation Solution

A self-signed implicit certificate is generated and operated upon using transformations similar to the Elliptic Curve Qu-Vanstone (ECQV) protocol, allowing a root CA to distribute its public key efficiently without the need for explicit self-signed certificates, thereby initiating a chain of trust while offering bandwidth savings.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional explicit certificates are used for root CA public key distribution, then authentication verification is complete and secure, but bandwidth usage increases due to larger certificate size

Engineering Contradiction:
Improveauthentication verificationVSAvoidbandwidth usage
Core Design Contradiction:
ReliabilityVSLoss of energy

Solution Approach 1:

The patent extracts the essential authentication verification mechanism from the traditional explicit certificate structure. Instead of transmitting the full explicit certificate with CA signature, the system uses implicit certificates that contain only the necessary cryptographic elements (public key reconstruction value and certificate data) to enable verification through mathematical operations, thereby removing redundant data while preserving security

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent changes the cryptographic parameter representation from explicit signature formats to implicit mathematical relationships. By using elliptic curve cryptography parameters and implicit certificate structures, the system transforms the verification process from signature validation to mathematical computation, achieving both bandwidth efficiency and complete authentication verification

Inventive Principle:
Principle #35Parameter changes

2Loss of energy

If implicit certificates are used to reduce bandwidth usage, then certificate size decreases, but explicit verification of CA signature is lost

Engineering Contradiction:
Improvebandwidth usageVSAvoidexplicit verification
Core Design Contradiction:
Loss of energyVSReliability

Solution Approach 1:

The patent introduces a mathematical intermediary mechanism (the public key reconstruction value and certificate data relationship) that mediates between the implicit certificate structure and complete authentication verification. This intermediary enables the verification process to occur through cryptographic operations on the implicit certificate elements without requiring traditional explicit signature verification

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent replaces the mechanical signature verification process with cryptographic mathematical operations. Instead of explicitly verifying CA signatures through traditional cryptographic validation, the system uses mathematical computations on implicit certificate elements (hash operations, elliptic curve operations) to achieve equivalent or superior verification capabilities

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Reliability

If self-signed explicit certificates are generated for root CA, then authentication is established through trusted events, but operational complexity and transformation requirements increase

Engineering Contradiction:
Improveauthentication establishmentVSAvoidoperational transformations
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent enables the root CA to self-generate its public key through cryptographic operations on the implicit certificate elements without requiring external trusted events or manual intervention. The system uses the certificate data and public key reconstruction value to computationally derive the public key, making the authentication establishment process automated and self-service oriented

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The patent inverts the traditional certificate generation approach. Instead of generating an explicit certificate and then extracting the public key, the system generates the public key through cryptographic operations on implicit certificate elements, reversing the conventional workflow and simplifying the operational transformations required

Inventive Principle:
Principle #13The other way round (Inversion)

Data Source

PatentEP3079300B1Self-signed implicit certificates
Publication Date: 2018.09.05 CERTICOM CORP
  • EP3079300B1 patent drawingFigure 1
  • EP3079300B1 patent drawingFigure 2
  • EP3079300B1 patent drawingFigure 3

AI summary

A method of generating a first and a second root private key (kCAroot) and establishing a first (IC1CAroot) and a second (IC2CAroot) self-signed implicit certificate that can be operated on to obtain a first and a second corresponding root public key (Q1CAroot, Q2CAroot). The method is performed by a certification authority device (102) that issues certificates in a cryptographic system based on an underlying elliptic group of order n. The certification authority device (102) obtains a long-term root private key (rCAroot) and a corresponding public-key reconstruction value (BCA); obtains a first (ICA1) and a second (ICA2) certificate data; operates on the public-key reconstruction value and the first certificate data (ICA1) to obtain the first self-signed implicit certificate (IC1CAroot); operates on the public-key reconstruction value and the second certificate data (ICA2) to obtain the second self-signed implicit certificate (IC2CAroot); operates on the long-term private root key and the first self-signed implicit certificate to obtain the first root private key; and operates on the long-term private root key and the second self-signed implicit certificate to obtain the second root private key.