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Air pollution, traffic congestion, stress and accidents are common features of today's road transportation experience. New approaches to improving the efficiency and safety of transportation systems are therefore required. Existing work on safe high-speed motorway driving, however, either assumes that vehicles are driverless and/or is limited to local decision making or to one-lane-only reservation systems. This paper describes a novel approach to vehicle scheduling based on real-time hierarchical scheduling, local real-time coordination and real-time inter-vehicle communication. We describe a new model in which road users reserve variable-size slots on motorway lanes, which enables enforcement of timeliness guarantees and adaptive scheduling based on a combination of local and global decisions. We present the research challenges that must be tackled to ensure that this vision of managed motorways becomes a reality.

Intelligent Transportation Systems are characterised by a requirement for detailed information on extensive transport networks. This information is typically gathered from sensors deployed throughout the network and is used for management and maintenance operations.In this paper we present the design and prototype implementation of a context-aware route profiling application intended for use by road management authorities in the Republic of Ireland. Our design allows data from a variety of sources to be combined to generate detailed information on traffic flow and journey times along the national road network. This information can be tagged with relevant context data reflecting the conditions under which sensor data was collected. The set of relevant contextual information includes details on temporal, spatial, weather and road usage pattern contexts.The prototype implementation relies on GPS data from a fleet of probe vehicles. An evaluation of this prototype is presented along with a discussion on the benefits of using context-aware computing techniques in a real world scenario.

Traditional access control mechanisms rely on a reference monitor to mediate access to protected resources. Reference monitors are inherently centralized and existing attempts to distribute the functionality of the reference monitor suffer from problems of scalability.Cryptographic access control is a new distributed access control paradigm designed for a global federation of information systems. It defines an implicit access control mechanism, which relies exclusively on cryptography to provide confidentiality and integrity of data managed by the system. It is particularly designed to operate in untrusted environments where the lack of global knowledge and control are defining characteristics.The proposed mechanism has been implemented in a distributed file system, which is presented in this paper along with a preliminary evaluation of the proposed mechanism.