Isogeny-Based Cryptosystem Randomization Against Side-Channel Attacks

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Isogeny-based cryptosystems are vulnerable to side-channel attacks, which exploit unintended information leakage, and there is a need to enhance their security while maintaining competitive performance, power, and area efficiency, especially in the context of post-quantum cryptography.

Innovation Solution

The method introduces randomness into isogeny-based cryptosystems by utilizing random inputs and entropy pools to change intermediate elliptic curve points and scalars, and to select isogeny formulas, thereby randomizing the computational hierarchy with minimal overhead, using techniques such as random projective coordinate representations, isomorphisms, and scalar randomization in point multiplication operations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If randomness is added to isogeny-based cryptosystems to protect against side-channel attacks, then security is improved, but computational overhead increases

Engineering Contradiction:
ImprovesecurityVSAvoidcomputational overhead
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies parameter changes by modifying the representation of elliptic curve points from standard affine coordinates to random projective coordinates. This transformation introduces randomness into the computational parameters without fundamentally changing the cryptographic algorithm, thereby enhancing security against side-channel attacks while maintaining computational efficiency.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent uses random projective coordinate representations as an intermediary layer between the cryptographic operations and the physical implementation. This intermediary transformation obscures the direct relationship between input operations and physical side-channels (power consumption, timing), making it difficult for attackers to extract information without significantly increasing computational complexity.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If random projective coordinate representations are used to randomize intermediate computations, then resistance to side-channel attacks is improved, but computational operations become more complex

Engineering Contradiction:
Improveresistance to side-channel attacksVSAvoidcomputational operations complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent changes the parameter representation of elliptic curve points from affine coordinates (x, y) to random projective coordinates (X, Y, Z) where x = X/Z and y = Y/Z. This parameter transformation allows the same mathematical operations to be performed with randomized values, improving side-channel resistance while the projective coordinate system itself maintains computational efficiency for elliptic curve operations.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentUS11943353B2Randomization methods in isogeny-based cryptosystems
Publication Date: 2024.03.26 PQSECURE TECHNOLOGIES LLC
  • US11943353B2 patent drawing
  • US11943353B2 patent drawing
  • US11943353B2 patent drawing

AI summary

A computer processing system having an isogeny-based cryptosystem for randomizing computational hierarchy to protect against side-channel analysis in isogeny-based cryptosystems.