Leszek Lilien

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Cloud computing allows the use of Internet-based services to support business processes and rental of IT-services on a utility-like basis. It offers a concentration of resources but also poses risks for data privacy. A single breach can cause significant loss. The heterogeneity of “users” represents a danger of multiple, collaborative(More)
Entities (e.g., users, services) have to authenticate themselves to service providers (SPs) in order to use their services. An entity provides personally identifiable information (PII) that uniquely identifies it to an SP. In the traditional application-centric Identity Management (IDM) model, each application keeps trace of identities of the entities that(More)
We present a novel paradigm of opportunistic networks or oppnets in the context of emergency preparedness and response (EPR). Oppnets constitute the category of ad hoc networks where diverse systems, not employed originally as nodes of an oppnet, join it dynamically in order to perform certain tasks they have been called to participate in. After describing(More)
Mobile clients retrieve and update databases at servers. They use transactions in order to ensure the consistency of shared data in the presence of concurrent accesses. Transaction processing at mobile clients faces new challenges to accommodate the limitations of mobile environments, such as frequent disconnections and low bandwidth. Caching of frequently(More)
This chapter discusses two issues. First, we discuss characteristics and vulnerabilities of WSN that necessitate designing intrusion detection (ID) solutions specialized for WSN. Second, we identify research challenges in ID for WSN. We also identify a new type of attack on WSN, called phenomenon forging.
Microsel1sors operate under severe energy cOllstraints a'nd should be deployed in large numbers Wilhou! any pre-col/figuration. The maill contribution of this paper is a generalized selfclustering protocol, called Low-energy Localized Clustering (LLC).lt iucorporates the bestfeatllres of two other recently proposed self-configurirzg protocols for sensor(More)
Specialized ad hoc networks of unmanned aerial vehicles (UAVs) have been playing increasingly important roles in applications for homeland defense and security. Common resource virtualization techniques are mainly designed for stable networks; they fall short in providing optimal performance in more dynamic networks—such as mobile ad hoc networks(More)
Extending the period of operation (lifetime) of wireless sensor networks (WSNs) is one of the most critical issues. Their limitations are due to limited energy resources. Available research results reveal that significant improvement in WSN lifetime can be achieved by adding spares (spare nodes). At the moment of WSN deployment, the minimum required(More)