There are four Working Groups within STVL.
- STVL-WG1: Stream Cipher Development. The aim of this working group is to pursue the development of stream ciphers for academic and industry use. The aim is to develop synchronous and self-synchronising stream cipher. The European 5th Framework project NESSIE has demonstrated that the design of stream ciphers is not straightforward. Even though five stream ciphers from well-respected designers were submitted to NESSIE, none achieved the claimed security requirements. Further, industry typically relies on a handful of proposals (which are therefore very widely used) or a range of well founded but ad hoc (and often proprietary) design techniques. By providing the cryptographic community with alternative stream ciphers that have been thoroughly analysed, the ECRYPT Network of Excellence can have a significant impact on both the design, analysis, and adoption of future stream ciphers on a global scale.
- STVL-WG2: Algebraic Analysis. At the start this working group was dedicated to making a co-ordinated study into the security of the Advanced Encryption Standard (AES). Since the publication of the final report, the charter of the working group has been changed and it will now focus on the algebraic cryptanalysis of symmetric primitives. While this topic might have evolved from earlier work in this WG on the AES, the scope of this work is broader than either the AES or block ciphers. It is hoped that some of the work that will be completed in this working group may be helpful in understanding the capabilities of this kind of analysis when applied to block ciphers but to other primitives such as stream ciphers and perhaps even hash functions.
- STVL-WG3: Strategic Research. The aim of this working group is to provide a co-ordinated summary and review of ongoing research within the scope of the STVL. While this may include a review of the work within the targeted Working Groups (currently STVL-WG1 and STVL-WG2) it is anticipated that the bulk of the work considered within this Working Group will lie outside the scope of the targeted working groups. It is intended that the Strategic Working Group will identify new problems and areas of research from which additional Working Groups will be formed to strengthen that research effort. One particular area of interest will be the development of algorithms to support lightweight cryptography. This may lead to the launch of a multi-partner initiative for the development of a suite of lightweight cryptographic primitives. As cryptographic techniques are increasingly incorporated into cheap and highly constrained consumer devices, the attendant physical constraints on the amount of available memory and processing power become important factors for the suitability of different cryptographic algorithms.
- STVL-WG4: Hash Functions. This working group is dedicated to providing a collaborative research environment for the analysis and design of hash functions. It is clear that the integrity of this important cryptographic primitive has been compromised by recent work and this WG was spun-out from STVL-WG3: Strategic Research as a response to this. Work is ongoing around the world on a number of different hash function initiatives. In STVL-WG3 we hope to provide an environment whereby ECRYPT members can work together in pursuing the goals of other efforts, such as those of NIST, rather than being in direct competition. Our goal, therefore, is for the ECRYPT Network of Excellence to make a positive impact on the design, analysis, and adoption of future hash functions long after ECRYPT has finished its work.