Encryption and signatures are two of the most fundamental cryptographic tools, enabling private and authentic communication. Yet, their adoption in applications, such as email, distributed storage, digital rights management and health care systems, has been slow. A primary reason is that many common operations that arise when using these tools in practice create (sometimes insurmountable) key management problems. This research studies how to design encryption and signature schemes with greater key management flexibility.
In particular, this research focuses on situations where data encrypted (or signed) under one cryptographic key needs to be re-encrypted (or re-signed) under another cryptographic key by a semi-trusted proxy given special information. For example, suppose Alice wants her mail server to forward her encrypted email to Bob without being able to read her messages. Investigators will broaden the theoretical foundations of proxy re-cryptography and work with industry partners to evaluate their performance in practice. The research will study the application of proxy re-signatures for maintaining the integrity of dynamic content distribution of documents on the Web.
Graduate students and women researchers will be involved in all aspects of this project, collaborating on both the theory and practice. Techniques derived from this research will be incorporated into cryptography and computer security courses at both universities. Thus, this project will help develop future well-rounded scientists able to design and apply cryptographic tools.
