Software framework for managing heterogeneity in mobile collaborative systems

ABSTRACT

Heterogeneity aspects in mobile collaborative systems, such as differences in user's interest, semantic conflicts across different domains and representations, and disparate device capabilities, cause difficulties in developing software applications. One of the key problems for collaborative applications is maintaining a consistent shared state.In this paper, we describe a framework that manages several aspects of heterogeneity to maintain consistency across the collaborating sites. We assume graph data structure for application state representation. Our framework is based on structural and semantic mappings between graph structures. The mapping can be customized to meet different requirements through user-defined policies and rules. An important constraint is efficient use of scarce system resources.We describe several applications built using the framework to collaboratively share XML documents. The XML documents in our case are 2D/3D representations of virtual worlds. We also show the performance results of our framework which demonstrate its feasibility for mobile scenarios.

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INDEX TERMS

Primary Classification:
  H. Information Systems
  H.5 INFORMATION INTERFACES AND PRESENTATION (I.7)
      H.5.3 Group and Organization Interfaces
          Subjects: Collaborative computing

Additional Classification:
  D. Software
  D.2 SOFTWARE ENGINEERING
        D.2.10 Design**
            Subjects: Representation**
        D.2.12 Interoperability
            Subjects: Data mapping

  E. Data
  E.1 DATA STRUCTURES
      Subjects: Graphs and networks

  H. Information Systems
  H.2 DATABASE MANAGEMENT
      H.2.5 Heterogeneous Databases
          Subjects: Data translation**

General Terms:
Algorithms, Design, Experimentation, Performance

Keywords:
consistency maintenance, content adaptation, mobile computing, scene simplification, virtual worlds