Publications (4)0 Total impact
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Article: Mobilitätsmanagement im Überblick: Von 2G zu 3, 5G.
Praxis der Informationsverarbeitung und Kommunikation. 01/2004; 27:68-73. -
Conference Proceeding: Supporting Proactive Location-Aware Services in Cellular Networks.
Personal Wireless Communications, IFIP-TC6 8th International Conference, PWC 2003, Venice, Italy, September 23-25, 2003, Proceedings; 01/2003 -
Article: Context Provisioning In Cellular Networks
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ABSTRACT: When people interact with each other, they implicitly make use of context information while intuitively deducing and interpreting their actual situation. Compared to humans, IT infrastructure cannot easily take advantage of context information in interactions. Typically, context information has to be provided explicitly. For a service to be context-aware it must be able to transparently adapt its behaviour to the user's context. However, this assumes the acquisition, refinement, and dissemination of context. In cellular networks, the context provisioning is a complex and troublesome matter. It has to be organized in an inter-organizational manner, has to be adjusted to a variety of heterogeneous service platforms, and raises issues of massive scaling and data distribution. This paper proposes a conceptual framework for deploying context provisioning in cellular networks. By introducing different levels of abstraction, the framework eases the design, implementation, and operation of context provisioning. Furthermore, context provisioning is separated from service provisioning, i.e., both can be realized independently from each other, which supports the rapid creation and deployment of new services. In order to evaluate the proposed framework, an instant messaging service has been realized, which is also presented in this paper. -
Article: Quality of context: What it is and why we need it
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ABSTRACT: When people interact with each other, they implicitly make use of context in-formation while intuitively deducing and interpreting their actual situation. Com-pared to humans, IT infrastructures cannot easily take advantage of context infor-mation in interactions. Typically, context information has to be provided explic-itly. Recently, cellular network operators have been showing interest in offering Context-Aware Services (CAS) in the future. For a service to be context-aware it must be able to use context information in order to adapt its behavior or the content it provides. Examples of CASs are restaurant finders, tour guides and dating services. These services will depend on the availability of context infor-mation which must be provided at the right time, in the right quality, and at the right place. The quality of this context information is neither identical to Quality of Service (QoS), nor to the quality of the underlying hardware components, i.e., Quality of Device (QoD). Rather, the precision, probability of correctness, trust-worthiness, resolution, and up-to-dateness of context information form a new set of quality parameters which we call Quality of Context (QoC). In this paper, we will discuss what QoC is, what its most important parame-ters are and how QoC relates to QoS and QoD. These three notions of quality are unequal, but not unrelated. Based on several examples we will show the interde-pendence between them. We will argue that QoC as a new notion of quality is necessary to allow for the provisioning of CASs in an interorganizational manner.
