Games and Abstraction: The Science of Cyber Security

This proposal addresses the challenge "How do we make better security decisions?". Specifically we propose to develop new approaches to decision support based on mathematical game theory. Our work will support professionals who are designing secure systems and also those charged with determining if systems have an appropriate level of security -- in particular, systems administrators. We will develop techniques to support human decision making and techniques which enable well-founded security design decisions to be made.

We recognise that the emerging trend away from corporate IT systems towards a Bring-Your-Own-Device (BYOD) culture will bring new challenges and changes to the role of systems administrator. However, even in this brave new world, companies will continue to have core assets such as the network infrastructure and the corporate database which will need the same kind of protection. It is certainly to be expected that some of the attacks will now originate from inside the corporate
firewall rather than from outside. Our team will include researchers from the Imperial College Business School who will help us to ensure that our models are properly reflecting these new threats.

Whilst others have used game theoretic approaches to answer these questions, much of the previous work has been more or less ad hoc. As such the resulting
security decisions may be based on unsound principles. In particular, it is common to use abstractions without giving much consideration to the relationship between properties of the abstract model and the real system. We will develop a new game theoretic framework which enables a precise analysis of these relationships and hence provides a more robust decision support tool.

The call for proposals gives examples of research that could contribute to challenge of "How do we make better security decisions?".
We claim that our proposal addresses each of these:

1. techniques to support human decision making and/or to examine the underlying rationale driving expert security decisions:
this was the primary rationale for the development of game theory.
2. techniques that enable well-founded security design decisions to be made which are based on an underlying set of well-defined principles:
game theory is a mathematical theory and as such rigorous and well founded. We argue that in its application to cyber security there is some residual ad-hoc decisions used in the construction of the model. This proposal aims to replace this ad-hoc component by well defined principles based on abstraction.
3. techniques to enable rigorous assessment of whether a system carries an appropriate level of protection for the threat environment it faces:
we will introduce the concept of security capacity as an upper bound on the achievable level of security in a system. We will elaborate on this or similar concepts and test them on empirical data.
4. techniques that enable well-informed trade-offs between security and other business drivers such as cost, functionality etc:
classically the notion of payoff in game theory encompasses such techniques. Through our collaboration with the Business School we expect to develop realistic understanding of the true payoffs involved in both SMEs and large organisations.
5. techniques that allow security spend to be targeted so as to provide the best return on investment:
again this is a classical game theoretical aspect that we expect to better understand via our empirical studies.

In addition to progressing the state-of-the art in the theoretical underpinnings of the project, we will develop a number of proof-of-concept implementations which will be made available to the stakeholder community. It is also anticipated that Business School empirical studies will lead to new policy advice.