Publications :: Lehn01

Advanced Techniques in Personalized Information Delivery


While most of our day-by-day interactions with information systems are of pull-based nature, the availability of mobile information appliances like smart phones, PDAs, or even laptop computers demands permanent and personalized information supply without explicitly querying the information sources. This shift from pull- to push-based information delivery hides a tremendous potential as well as the risk of information flooding. Thus the need of systems providing a push-based and personalized information service is obvious.
In general we may distinguish four classes of personalized information services. The lowest class applies to broadcasting, where information is simply distributed to every consumer device. Either the end user or an appropriate application on his/her side is responsible for filtering and further processing. The next class of data dissemination provides a channel-based addressing scheme, where users register explicitly for certain channels. Every information fed to the selected channels by any information producer is forwarded to the end user without further filtering. Sample application scenarios may be seen in news- or stock-tickers. The third class of personalized information services may be considered the content-based filtering scheme provided by data notification services. In this context, the user may specify a predicate addressing the relevant information with regard to a certain channel, thus providing extensive information filtering.
All these concepts covered by broadcast, dissemination or notification preserve the original messages produced by the publisher. Any further processing like combining information from multiple information sources or aggregating numerical or textual information is not supported. Therefore the class of subscription systems allows users to register complex queries in combination with specific delivery criteria. Once messages are produced by publishing components, they are integrated into a publication-consistent global database and propagated to the appropriate subscribers. The application context, the resulting requirements, the existing technologies, and advanced strategies from a modeling as well as implementional perspective are the focus of this report.


Last Update: August 29, 2011 22:37 CEST
Author Database Technology Group, Technische Universität Dresden

Prof. Dr.-Ing.
Wolfgang Lehner

Tel.: +49 351 463-38383
Fax: +49 351 463-38259

Visiting Address (View)
Nöthnitzer Str. 46
Room 3109
01187 Dresden

Postal Address
Technische Universität Dresden
Dep. of Computer Science
Institute for System Architecture
Database Technology Group
01062 Dresden