In our digitized world, data security and privacy have become paramount concerns. As data breaches and cyberattacks continue to make headlines, there is a growing demand for more practical cryptographic solutions. A promising such solution is attribute-based encryption (ABE). ABE allows users to manage access to their data in a flexible way. In particular, they can choose, based on the attributes of the intended recipients, who are granted access to their data and who are denied. Because ABE achieves this cryptographically, this type of access control is enforced directly on the data, which can be stored anywhere, without requiring a constant interaction with any authorities. However, despite the many advancements in developing ABE, it is still difficult to find an implementation that satisfies all the requirements posed by many real-world applications. In this thesis, we study the state of the art in ABE with the aim to breach this gap, and simplify the design (and ultimately, the implementation) of schemes that satisfy all such requirements. We also improve existing work to enable better and more flexible efficiency features. In this way, we help make ABE more practical as a means to achieve data security and privacy.
Marloes Venema obtained her bachelor’s degree in Mathematics in 2016 and her master’s degree in Computing Science in 2018. Since 2018, she has been working on the theoretical design and analysis of various cryptographic primitives, with the aim to make them practical enough for real-world settings. In particular, during her PhD, she has focused mainly on attribute-based encryption, which has ultimately led to this dissertation.