Scalable Cryptography

• Applicant: Professor Dr. Eike Kiltz, since 2/2020
• Subject Area: Theoretical Computer Science
• Term: from 2014 to 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 254950907

In our modern digital society, cryptography is vital to protect the secrecy and integrity of transmitted and stored information. Settings like digital commerce, electronic banking, or simply private email communication already rely on encryption and signature schemes.However, today's cryptographic schemes do not scale well, and thus are not suited for the increasingly large sets of data they are used on. For instance, the security guarantees currently known for RSA encryption - the most commonly used type of encryption scheme - degrade linearly in the number of users and ciphertexts. Hence, larger settings (such as cloud computing, or simply the scenario of encrypting all existing email traffic) may enable new and more efficient attacks.To maintain a reasonable level of security in larger scenarios, RSA keylengths must be chosen significantly larger, and the scheme becomes very inefficient. Besides, a switch in RSA keylengths requires an update of the whole public key infrastructure, an impossibility in truly large scenarios. Even worse, when the scenario grows beyond an initially anticipated size, we may lose all security guarantees.The "Scalable Cryptography" project running since October 2014 specifically aims to construct cryptographic schemes that scale well to large scenarios. We could already develop several practical cryptographic schemes suitable for truly large settings. We now apply for an extension of the project, in order to (a) fully exploit the potential of the techniques developed in the first phase of the project, and to (b) address promising new research avenues discovered in the course of the project so far.In this proposal, we detail the accomplishments of the initial "Scalable Cryptography" project, and how a possible renewal could affect the outcome of this project.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1736: Algorithms for Big Data
• Ehemaliger Antragsteller: Professor Dr. Dennis Hofheinz, until 1/2020