Experts in Analyzing the Security of Symmetric Cryptographic Primitives
The IAIK Krypto research group focuses on the design and security analysis of symmetric cryptographic primitives. For this purpose, we apply and adapt existing mathematical frameworks to practical designs and design methods. We conduct basic and applied research and offer consulting services.
We are part of the Secure Entities for Smart Environments (SEnSE) Group at the IAIK.More about SEnSE »
Current Research Topics
- Authenticated Encryption
Whenever two parties communicate over a network, they typically have two central security requirements: to keep unauthorized third parties from reading confidential data, and to assert the integrity and authenticity of the received data. An authenticated encryption algorithm provides both of these essential security features, confidentiality and authentication of the data. In most applications, there is not much value in keeping data secret if it is not authenticated. Authentication of data is often of more value than its confidentiality.
While ciphers and hash functions receive a great deal of attention from the cryptographic community due to such high-profile competitions as NIST's AES and the SHA-3 selections as well as ECRYPT's eSTREAM project, authenticated encryption schemes and message authentication codes have been arguably less popular among researchers. However, with the CAESAR project on track, there is a growing need for fundamental and applied research to support the choice of a portfolio of new authenticated encryption algorithms that will be secure for the next decades.
For more information visit the CAESAR website here.
- Cryptographic Hash Functions
Cryptographic hash functions play a fundamental role in modern information security. Already in 1976, Diffie and Hellman identified the need for a one-way hash function as a building block for a digital signature scheme. Today cryptographic hash functions are deployed in a large number of applications, protocols and cryptographic schemes. They are used for instance for digital signatures, password protection, random number generation, key derivation, integrity protection, malicious code detection, message authentication, and many more.
In the last years, much progress has been made in the cryptanalysis of hash functions. Weaknesses have been shown for most of the commonly used hash functions like MD5 and SHA-1. As a consequence, NIST has decided to organize a public competition in order to design a new hash function, leading to the selection of Keccak as SHA-3 in October 2012. However, with the cryptographic community joining forces in the SHA-3 competition, the SHA-2 family got considerably less attention in the last few years. Since NIST explicitly recommends both, SHA-2 and SHA-3, the cryptanalysis of SHA-2 and SHA-3 is of great interest to get a good view on their security margin.
For more information on the SHA-3 competition visit the website here.
- AES Security and Implementations
The challenge in cryptographic research is to construct mathematical transformations that have desirable security properties on the one hand, but on the other hand they should also be efficiently realizable in hardware and/or software. The most interesting event of the end of the 1990's in this respect was doubtlessly the selection process for a new encryption standard AES by NIST.
The Advanced Encryption Standard (AES) competition received submissions, evaluations and other contributions from all over the world. Even after the selection of the AES, the research continues. The development of new cryptanalysis techniques necessitates continuous re-evaluation of the security. The introduction of new applications puts new demands on implementations and requires rethinking the possibilities for optimization of performance, energy consumption, cost, … We study AES extensively both from the security and the implementation viewpoint. An overview of the research on AES is available at our AES Lounge.