[Resource Topic] 2018/016: New Techniques for Public Key Encryption with Sender Recovery

Welcome to the resource topic for 2018/016

New Techniques for Public Key Encryption with Sender Recovery

Authors: Murali Godi, Roopa Vishwanathan


In this paper, we consider a scenario where a sender transmits ciphertexts to multiple receivers using a public-key encryption scheme, and at a later point of time, wants to retrieve the plaintexts, without having to request the receivers’ help in decrypting the ciphertexts, and without having to locally store a separate recovery key for every receiver the sender interacts with. This problem, known as public key encryption with sender recovery has intuitive solutions based on hybrid encryption-based key encapsulation mechanism and data encapsulation mechanism (KEM/DEM) schemes. We propose a KEM/DEM-based solution that is CCA2-secure, allows for multiple receivers, only requires the receivers to be equipped with public/secret keypairs (the sender needs only a single symmetric recovery key), and uses an analysis technique called plaintext randomization that results in greatly simplified, clean, and intuitive proofs compared to prior work in this area. We instantiate our protocol for public key encryption with sender recovery with the Cramer-Shoup hybrid encryption scheme.

ePrint: https://eprint.iacr.org/2018/016

See all topics related to this paper.

Feel free to post resources that are related to this paper below.

Example resources include: implementations, explanation materials, talks, slides, links to previous discussions on other websites.

For more information, see the rules for Resource Topics .