Article in Proceedings INPROC-2010-32

BibliographyGeiger, Lars; Dürr, Frank; Rothermel, Kurt: Aggregation of User Contexts in Context-based Communication.
In: Proceedings of the 6th Euro-NF Conference on Next Generation Internet (NGI 2010).
University of Stuttgart : Collaborative Research Center SFB 627 (Nexus: World Models for Mobile Context-Based Systems).
pp. 1-8, english.
Paris: IEEE Xplore, June 2010.
Article in Proceedings (Conference Paper).
CR-SchemaC.2.1 (Network Architecture and Design)
C.2.2 (Network Protocols)
C.2.4 (Distributed Systems)
C.2.6 (Internetworking)

A context-based communication system enables the indirect addressing and routing of messages according to the users' contexts. This provides, for example, the means to send a message to all students on campus who attend a certain class, with information about an upcoming exam. However, for a targeted forwarding of messages towards users, the routers need information about the context of connected users. Global knowledge, i.e., each router knowing about every user, is not scalable, though, because of the necessary update messages to keep this information up-to-date.

To address this challenge, a router can aggregate similar contexts and only provide such an aggregated view to neighboring routers. In this paper, we present an approach to aggregate similar contexts, based on a similarity measure for user contexts. The algorithm can be adjusted according to the observed messages and user contexts in the system by specifying a similarity threshold to determine when contexts are aggregated.

The aggregation of user contexts improves the scalability of our approach by significantly reducing the load of context updates by up to 30%, depending on the usage of the system. This improvement comes at the cost of a negligible increase in false positive messages due to the loss of information used for forwarding messages.

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Department(s)University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems
Project(s)SFB-627, A2 (University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems)
Entry dateMay 14, 2010
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