The UK’s National Cyber Security Centre has just published its white paper on “Advanced Cryptography,” which is characterized as “cryptographic methods for processing encoded information, providing enhanced capabilities beyond what traditional cryptography offers.” It encompasses techniques such as homomorphic encryption, attribute-based encryption, zero-knowledge demonstrations, and secure multiparty computations.

It’s packed with valuable recommendations. I particularly value this caution:

When contemplating the adoption of Advanced Cryptography, begin with a precise definition of the issue, utilizing that to steer the creation of a suitable remedy. In other words, you should not commence with an Advanced Cryptography method and then try to adapt the functionality it offers to the issue.

Additionally:

In nearly all situations, it is poor practice for individuals to create and/or execute their own cryptography; this is even more applicable to Advanced Cryptography than to conventional cryptography due to the intricacies of the algorithms. This caution also pertains to developing your own application based on a cryptographic library that employs the Advanced Cryptography fundamental operations, as subtle mistakes in their application can lead to significant security vulnerabilities.

The summary:

Advanced Cryptography encompasses a variety of methods for safeguarding sensitive information at rest, during transmission, and while in use. These methods enable innovative applications with varied trust dynamics between the involved parties, in contrast to traditional cryptographic approaches for encryption and authentication.

Nonetheless, several considerations must be addressed before implementing a solution based on Advanced Cryptography, including the relative underdevelopment of the techniques and their applications, considerable computational demands and delayed response times, as well as the possibility of introducing additional cyber attack pathways.

Efforts are currently in progress to standardize certain forms of Advanced Cryptography, and the effectiveness of implementations is continually advancing. While numerous data processing challenges can be resolved with conventional cryptography (which generally leads to a more straightforward, cost-effective, and seasoned solution), for those that cannot, Advanced Cryptography methods may eventually facilitate novel ways to leverage extensive shared datasets without jeopardizing individual privacy.

NCSC blog entry.