Large Scale Network-Centric Distributed Systems

6

Middleware Support for Context Handling and Integration in Ubiquitous Computing

Frederico Lopes, Paulo F. Pires, Flávia C. Delicato, Thais Batista, and Luci Pirmez

Contents

6.1 Introduction

6.2 Ubiquitous Computing

6.3 Middleware for Ubiquitous Computing

6.3.1 Approaches and Techniques

6.3.2 Existing Middleware Platforms

6.4 A Solution to Integrating Context Provision Middleware for Ubiquitous Computing

6.4.1 Overview

6.4.2 Terminology

6.4.2.1 Services

6.4.2.2 Semantic Workflow

6.4.2.3 Execution Plan

6.4.3 Context Model

6.4.4 Architecture

6.4.5 Service Metadata

6.4.6 Workflow Specification

6.4.7 Execution Plan Selection

6.5 Conclusion

Acknowledgments

References

6.1 Introduction

The term ubiquitous computing (UC) denotes a recent, post-desktop, model of human–computer interaction in which information processing has been thoroughly integrated into everyday objects and activities in a way that the computational elements become invisible to the user.¹ Ubiquitous computing [1] encompasses sensor-instrumented environments, which are often endowed with wireless network interfaces, in which devices, software agents, and services are integrated in a seamless and transparent way and cooperate to meet high-level goals of human users. Ubiquitous environments may range from small-scale systems, comprising only applications and devices involved in a personal area network (PAN), to large-scale systems, encompassing physically distributed devices and applications and heterogeneous networks, ...