Enabling Proactivity in Context-aware Middleware Systems by means of a Planning Framework based on HTN Planning

Abstract

Today's context-aware systems tend to be reactive or 'pull' based-the user requests or queries for some information and the system responds with the requested information. However, none of the systems anticipate the user's intent and behavior, or take into account his current events and activities to pro-actively 'push' relevant information to the user. On the other hand, Proactive context-aware systems can predict and anticipate user intent and behavior, and act proactively on the users' behalf without explicit requests from them. Two fundamental capabilities of such systems are: prediction and autonomy. In this paper, we address the second capability required by a context-aware system to act proactively i.e. acting autonomously without an explicit user request. To address it, we present a new paradigm for enabling proactivity in context-aware middleware systems by means of a Planning Framework based on HTN planning. We present the design of a Planning Framework within the infrastructure of our intelligent context-aware middleware called Rover II. We also implement this framework and evaluate its utility with several use cases. We also highlight the benefits of using such a framework in dynamic ubiquitous systems.