The aim of the EurEauWeb is to develop an information system for users of the European Waterways. Boaters, Anglers or hikers, which drive on or walk along the waterways, are interested in getting up to date information about their current location and about possible destinations. Furthermore, boat operators and official authorities are interested in staying in contact with boat hirers and users, e.g. to monitor the boat status or to handle emergency situations.
Therefore, the requested information ranges from e.g. general description of a city, to very specific information, e.g. waiting times at the next lock.

Due to the wide range of interests it is necessary to have an open, service based system architecture. Such an architecture guarantees that several service and content providers can contribute information to the EurEauWeb system.
Users have the following possibilities to access the EurEauWeb system:

• EurEauWeb Mobile
  The EurEauWeb Mobile consists of components for service access and visualization of location based information, e.g. to display an overview map of the current area and include all marinas that have a filling station. The client can be used on mobile devices like PDAs and Laptops as well as on a stationary PC.
• EurEauWeb Portal
  EurEauWeb services can also be accessed from every computer via the Web Portal, which provides a functionality similar to the one of the client application.

The project addresses several technology areas like location aware information, mobile access to complex information, service discovery and service integration.

IPSIs contribution to the project is the design of service infrastructures, as well as a system for dynamic discovery of and access to those services. Additionally, IPSI develops scalable and robust methods for the access to data sources from mobile devices to accomplish up to date information. Also, schemes for handling of heterogeneous and evolving XML data are developed.

Up-to-date information
Users expect "high quality" information from systems like EEW. However, such a system is difficult to realize. In the simplest case, information is requested over and over again "from scratch" from providers, i.e. the user has no data and has to download every piece of information with a conscious action. Hereby it is also as-sumed that the provided information itself is up to date. But, communication restrictions like low bandwidth and unstable radio communication hamper the possibility to quickly obtain up-to-date information on demand.
Hence, it is important to utilize the communication channel evenly by pre-fetching, pre-loading and caching relevant data in a transparent manner. The development of query processing support for an efficient combining of local and remote data is therefore necessary.

Relevance of information
The relevance of information plays an important role to reduce the amount of communication and provide low response times of the system. The transmission of unnecessary information, which does not match with the users interests, should be avoided.
The user profile, which describes exactly what is relevant for the user, portrays an important part of the information selection. To provide this functionality it will be necessary to enrich the information with meta-data. Such meta-data describes individual information records, and enables the user to download solely relevant information.

Distribution of location aware information
Location is an important part of the information selection for travelling users. The current user position, given by a positioning system, is part of the users profile. Hence, during the journey, information has to be updated regularly according not only to the profile, but also to the current position. Moreover, ad hoc queries on other locations are necessary, e.g. to get information about an upcoming port. Therefore, the provided information has to be enhanced with location data, and the databases have to support queries that combine general attributes with geo-graphical (spatial) attributes.

Reliable mobile access to complex information
The users of information systems trust on the system to provide them with complete information. For traditional systems with direct connection such guarantees can easily be given, as the communication is very reliable. In contrast, mobile communication systems are more instable. Hence, the data management has to accomplish data consistency and performance with low communication over-head. Communication gaps have to be filled with locally stored information, or the user has to be notified about the incompleteness of data.

Service discovery
Service discovery and service information trading provide basic mechanisms that allow services to be automatically found or announced. Here, services are to be understood as for example a content provider, hotel reservation or repair shops. Service providers try to announce their services by registering with a service information trader (which providers have to find first). Service users query the service information trader(s), and can select relevant services through use of Boolean expressions. After a successful query the user applies the service information in or-der to run the service. In this manner, the service information trading enables integration of services at runtime in the system.

Integration of Services
For systems like EEW, which are based on distributed services, service composition is an integral part. The results of different services can be combined to enrich the end result that is presented to the user. The integration of services can be done locally on the device as well as by another service, e.g. service A can en-hance the maps of service B with water level information of service C.

Lightweight Communication
Communication is a basic prerequisite for the user obtaining access to up-to-date information that is being supplied by one or several servers. In many existing sys-tems it could be seen, that communication precisely in conjunction with mobility is not easy to realize, since radio is an unstable medium. The starting point for an op-timal and efficient transmission of data is a lightweight protocol for data commu-nication, operating over a narrowband radio channel. Due to the instability of the radio medium, it is necessary to buffer the user requests and - according to user preferences - send them by a permanent or temporary communication channel. Additional aspects like security or logging must also be taken into consideration.

Scalability and Robustness
Scalability means that the response times of the system are independent from the number of users and services. The system must also be as robust as possible such that user can rely on the system. Thus, scalability and robustness are major design goals for the EurEauWeb system. The challenges are the mobile communication with narrowband radio channels and the load balancing of frequently accessed services, e.g. service discovery or mapping.

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  Human Factors Research Group, Ireland
  
  University College Cork, Ireland



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  Fraunhofer IPSI, Germany



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  Softeco Sismat, Italy



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  British Waterways, UK



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  Centro di Ricerca, Sviluppo e Studi Superiori in Sardegna, Italy



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  Radicalmedia, Portugal



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  Euromapping, France



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  Lancell Systems, Spain



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  Marketing Campaigns, UK



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  DMYV - Deutscher MotorYacht-Verband e.V., Germany



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  Fieldfare Trust, UK



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  Viking Afloat, UK



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  France Afloat Burgundy Cruisers, France



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  Shannon Castle Line, UK