Composably secure device-independent encryption with certified deletion
Abstract
We study the task of encryption with certified deletion (ECD) introduced by Broadbent and Islam (2020), but in a device-independent setting: we show that it is possible to achieve this task even when the honest parties do not trust their quantum devices. Moreover, we define security for the ECD task in a composable manner and show that our ECD protocol satisfies conditions that lead to composable security. Our protocol is based on device-independent quantum key distribution (DIQKD), and in particular the parallel DIQKD protocol based on the magic square non-local game, given by Jain, Miller and Shi (2020). To achieve certified deletion, we use a property of the magic square game observed by Fu and Miller (2018), namely that a two-round variant of the game can be used to certify deletion of a single random bit. In order to achieve certified deletion security for arbitrarily long messages from this property, we prove a parallel repetition theorem for two-round non-local games, which may be of independent interest.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jul 06, 2023
- Source ID
- 10.22331/q-2023-07-06-1047
Entities
People
- Ernest Y.-Z. Tan
- Srijita Kundu
Organizations
- Air Force Office of Scientific Research
- ETH Zurich
- Ministry of Education
- National Research Foundation
- Swiss National Science Foundation
- University of Waterloo