
Public-key encryption (PKE) has revolutionized cryptography, by allowing remote parties to communicate secretly. The down side of PKE is to maintain long lists of public keys in public-key directories. Identity-based encryption (IBE) gives a way around such lists by allowing one master public key and people’s unique names (e.g. , their email addresses) to be their public-key. The down side of IBE is that the issuer of the master public- key (and decryption keys) can decrypt all the messages, leading to the well-known key escrow problem with IBE. In this talk, I will introduce registration based encryption, which is a hybrid encryption method connecting IBE and PKE, getting (most) the benefits of both, without suffering from long key directories nor the key escrow problem. Based on joint (TCC and PKC 2019) works with Sanjam Garg, Ahmadreza Rahimi, Mohammad Hajiabadi, and Sruthi Sekar.

Associate Professor, University of Virginia