A Service-Based Architecture for In-Vehicle Telematics Systems D. Reilly and A. Taleb-Bendiab {D.Reilly, A.Talebbendiab}@livjm.ac.uk http://www.cms.livjm.ac.uk/emergeits Abstract The growing needs to access information in remote, mobile environments have sparked interests in so-called In- Vehicle Telematics Systems (IVTS) [1]. These relatively new systems have the potential to deliver computing facilitates to road vehicles, which may include in-vehicle infotainment, route-guidance and navigation and the provision of vital information resources used by fleet haulage companies and emergency services (police, fire and ambulance). This paper describes the EmergeITS 1 project, which is concerned with the use of IVTS for emergency fire service applications. In particular, the paper describes a distributed service-based architecture, based on the Jini middleware technology, which can be used to provide fault tolerant application services to remote in-vehicle computers and mobile devices such as Palm devices and WAP phones. 1. Introduction In-Vehicle Telematics Systems (IVTS) combine mobile computing and telecommunications technologies to provide computing facilities within road-vehicles. IVTS may combine the use of small footprint mobile computers, running Windows CE, Palm devices and WAP phones. Centralized computing facilities and other remote systems are accessed through wireless links using GSM or WAP technologies. IVTS applications range from private vehicle owners, concerned with a pleasant, congestion-free journey, to fleet management and automatic vehicle location (AVL) for commercial companies right through to the emergency services (police, fire and ambulance) concerned with remote access of vital corporate information systems crucial to saving lives! IVTS occur as distributed heterogeneous systems, which suggests a need for a distributed software architecture capable of gathering information about the operational context and mobile communication environment to “auto- configure” systems by adapting behaviour according to context and environment [2]. Middleware technologies such 1 EmergeITS is a collaborative project between the School of Computing and Mathematical Sciences at Liverpool John Moores University and Merseyside Fire Service (MFS) as CORBA, DCOM and Jini [3] play a crucial role in such an architecture by providing APIs and support utilities that bridge the gap between network operating system and distributed components and services. The remainder of this paper describes the service-based EmergeITS architecture, which uses Jini middleware to allow Merseyside Fire Service (MFS) to access centralized information systems as reliable, easy to use application services through in-vehicle mobile computers and Palm devices. 2. Jini Middleware Technology The idea of middleware is not new and IBM’s CICS is an early example of transaction-oriented middleware. Current object-oriented middleware technologies rely on distributed objects and “stubs” or proxies through which objects can communicate using remote method invocation (RMI) and remote events. A higher-level service-oriented abstraction is often used in object-oriented middleware, which regards a service as a logical concept such as a printer service or chat- room service. This abstraction is used extensively in the Jini middleware technology, which provides an API that allows clients to use services through lookup, discovery and RMI mechanisms. Jini applications essentially consist of three things: application services, clients and lookup services and code can be moved around, or “marshalled”, between the three. Clients discover services by downloading a remote stub or proxy, implemented as a Java interface, and use Java’s RMI to interact with the service through the proxy. Jini/RMI was selected as the middleware technology for EmergeITS, due to its capabilities to manage services remotely through leasing and activation mechanisms were the latter provides capabilities to implement “lazy” services, which are activated or started on demand. 3. EmergeITS Architecture The main aim of EmergeITS was the development of a service-based architecture capable of managing application services, used by remote vehicles, according to the following requirements: 1. The architecture was to be suitable for use over a wireless link (2-3 sq. miles) with minimum intervention from the user.