Source URL: https://www.schneier.com/blog/archives/2025/05/ncsc-guidance-on-advanced-cryptography.html
Source: Schneier on Security
Title: NCSC Guidance on “Advanced Cryptography”
Feedly Summary: The UK’s National Cyber Security Centre just released its white paper on “Advanced Cryptography,” which it defines as “cryptographic techniques for processing encrypted data, providing enhanced functionality over and above that provided by traditional cryptography.” It includes things like homomorphic encryption, attribute-based encryption, zero-knowledge proofs, and secure multiparty computation.
It’s full of good advice. I especially appreciate this warning:
When deciding whether to use Advanced Cryptography, start with a clear articulation of the problem, and use that to guide the development of an appropriate solution. That is, you should not start with an Advanced Cryptography technique, and then attempt to fit the functionality it provides to the problem. …
AI Summary and Description: Yes
Summary: The UK’s National Cyber Security Centre (NCSC) white paper on “Advanced Cryptography” discusses modern cryptographic techniques that enhance data security, such as homomorphic encryption and zero-knowledge proofs. It advises against users creating their own cryptographic solutions, emphasizing the complexity of these advanced methods. The paper highlights the benefits, challenges, and future potential for improving data privacy without compromising security.
Detailed Description:
The white paper by the NCSC outlines crucial aspects of Advanced Cryptography, which consists of innovative cryptographic techniques designed to handle encrypted data securely and effectively. Here are the major points covered in the document:
– **Definition and Techniques**:
– Advanced Cryptography includes methodologies such as:
– Homomorphic encryption: allows computations to be performed on encrypted data without needing to decrypt it.
– Attribute-based encryption: enables access control based on user attributes.
– Zero-knowledge proofs: allows one party to prove to another that a statement is true without revealing any additional information.
– Secure multiparty computation: enables parties to jointly compute functions over their inputs while keeping those inputs private.
– **Implementation Warnings**:
– Practical advice is provided, particularly highlighting:
– The necessity to clearly define the problem before selecting an Advanced Cryptography solution, discouraging the approach of fitting a solution to a problem after choosing a technique.
– The dangers of users designing their own cryptographic methods, emphasizing the complexity involved in Advanced Cryptography makes self-implementation even riskier than traditional methods.
– **Applications and Considerations**:
– Advanced Cryptography addresses the protection of sensitive data across various states:
– **At rest**: securing data stored on devices.
– **In transit**: protecting data as it moves across networks.
– **In use**: safeguarding data while processed.
– It enables innovative applications by introducing different trust relationships compared to conventional encryption.
– **Challenges and Risks**:
– Several factors must be considered before deployment, such as:
– The still-developing nature of these techniques, leading to potential inefficiencies and higher computational demands.
– Potential vulnerabilities that new mechanisms may introduce, including new attack vectors.
– **Future Developments**:
– The white paper mentions initiatives to standardize Advanced Cryptography techniques and highlights the continuous improvement of their implementations.
– While traditional cryptography solves most data processing needs effectively, Advanced Cryptography could open new approaches without sacrificing user privacy.
This white paper is highly relevant for professionals in the fields of cloud computing, information security, compliance, and cryptographic applications, providing insights into the evolving landscape of data protection technologies.