My most significant recent work is in the field of applied topology. While the early development of topology was firmly rooted in applications, many of its later advances have been driven by purely mathematical motivations. More recently there is a growing awareness that some of its powerful tools may be just what is needed to help address outstanding problems in diverse modern applications. I ...

Adaptive security systems aim to protect valuable assets in the face of changes in their operational environment. They do so by monitoring and analysing this environment, and deploying security functions that satisfy some protection (security, privacy, or forensic) requirements. In this paper, we suggest that a key characteristic for engineering adaptive security is the topology of the operatio...

There is currently a lot of work in Ambient Intelligence – or AmI – reporting on specific scenarios, or on implementations of particular cases. In the same time, there is a common agreement of the fact that AmI applications should be pervasive, covering a large number of devices, assisting a large number of people, and serving a large number of purposes. In an attempt to achieve scalable scenar...

In this paper we propose a new routing protocol called virtual sink rotation (VSR) routing for large-scale sensor networks. VSR can efficiently handle a large number of sources as well as a large number of sinks with potential mobility. Each sensor node is not required to know the global network topology nor the location awareness. The main ideas underlying the VSR are two folds. First, to alle...

In this paper, we propose to fuse two main enabling features in cognitive radio systems (CRS): spectrum sensing and location awareness in a single compressed sensing based formalism. In this way we exploit sparse characteristics of primary units to be detected, both in terms of spectrum used and location occupied. The compressed sensing approach also allows to overcome hardware limitations, in ...

Embedding of virtual network (VN) requests on top of a shared physical network poses an intriguing combination of theoretical and practical challenges. Two major problems with the state-of-the-art VN embedding algorithms are their indifference to the underlying substrate topology and their lack of reoptimization mechanisms for already embedded VN requests. We argue that topology-aware embedding...

New challenges and problems emerge everyday with the current wave of terrorism. Suicide bombing, and explosions – a phenomenon only believed to be exist in the battlefields – witnessed and experienced by thousands in civil settings. Traditional approaches and conventional solutions often fail to understand the emerging problems, and help us mitigate the effects. When modeling explosions for inv...

Localization arises repeatedly in many location-aware applications such as navigation, autonomous robotic movement, and asset tracking. Analytical localization methods include triangulation and trilateration. Triangulation uses angles, distances, and trigonometric relationships to locate an object. Trilateration, on the other hand, uses only distance measurements to identify the position of the...