A Post-Quantum End-to-End Encryption Protocol
Shashvat Sharma, Meenakshi Tripathi, Harish Kumar Sahu, Ashish Karan · 2023
Because of Shor’s method, it is expected that quantum computers will have the capability to decipher current public key encryption methods. Consequently, there is a need to replace existing public key cryptography with quantum-resistant cryptography, also known as post-quantum cryptography (PQC) algorithms. In the last twenty years, significant progress has been made in the field of PQC research, leading to the creation of various algorithms that are proven to be resistant to quantum attacks. Several organizations responsible for standardization have already selected and are in the process of standardizing specific PQC algorithms.In popular instant messaging and voice-over IP applications like Signal, Facebook Messenger, and WhatsApp, the Signal Protocol provides end-to-end encryption (E2EE) and additional security features such as forward secrecy, future secrecy, authentication, asynchronous communication, and deniability. The protocol utilizes the ECDH Curve25519 key exchange and hash-based key derivation algorithms to accomplish this. However, the ECDH key exchange is vulnerable to attacks from quantum computers, which can compromise the security of contemporary cryptographic techniques by obtaining the corresponding public keys. Therefore, there is a need to replace the ECDH key exchange with a quantum-safe key exchange scheme that is resistant to attacks from quantum computers.In this context, the focus is on investigating post-quantum cryptography (PQC) that can provide robust security against quantum computing threats and proposing an end-to-end encryption scheme.