Adaptive Middleware Services for Situation-Aware Communication in Ubiquitous Computing Environments 
[RCSM Middleware Research Project]
Department of Computer Science and Engineering
Arizona State University

An Overview

A major trend in distributed computing is towards environments consisting of numerous wearable, handheld, and embedded devices. Rapid growth in inexpensive, short range, and low-power wireless communication hardware and network standards are now enabling experimentation with ubiquitous computing (ubicomp) environments. Ubicomp environments focus on integrating computers with the physical environment and everyday lives, essentially making computing and communication transparent to the users. Ubicomp applications have the following characteristics: 1) Context-sensitivity (or context-awareness) is the ability of a device to detect its current context and changes in contextual data; 2) Situation-awareness provides applications the ability to capture and analyze the context and interrelationship between users’ actions and devices, and 3) Ad hoc ephemeral group communication: Group communication channels among applications tend to be instantaneously established and terminated due to changing contexts, node mobility, and resource availability.

These issues should be investigated from middleware-service perspective since a middleware provides a standardized way to address interoperability, development, and runtime support for a wide variety of distributed applications in heterogeneous environments. Further, it is expected that the devices in ubicomp environments will be resource poor. 

We are taking an integrated hardware and software approach in developing following essential services to enable situation-aware and adaptive communication in ubicomp environments:

• Situation-aware communication: We are investigating a fundamentally new paradigm of inter-object communication using the situation and context of the corresponding devices. A situation-aware Object Request Broker (ORB), a situation-aware interface definition language (IDL), and related object communication frameworks are being developed in this aspect.

• Ephemeral group management: We are looking at an efficient group management service to enable the establishment of device communities, which will use situation as the collaboration agreement. A situation-triggered group communication service with impromptu group addressing scheme will be developed to facilitate ad hoc formation of communities of devices.

• Autonomous coordination for information dissemination: Finally, we are also investigating the feasibility of using cellular automata computational model to design a simple, energy efficient, and scalable information dissemination service, which will allow the devices to use simple coordination rules to enable globally complex interactions.

The novelty of the proposed approach spans across ubiquitous computing, networking, and middleware, tying these areas in fundamentally new ways. First, the proposed research will integrate situation-awareness and ad hoc group communication to provide a sufficient basis for a new breed of collaborative ubicomp applications. Second, the research is based on our ongoing work on RCSM, which is a Reconfigurable and Context-Sensitive Middleware, employing a fundamentally new and alternative approach to next generation embedded middleware design using software and reconfigurable FPGA hardware (Field Programmable Gate Arrays) to address both customizability and improved performance for heterogeneous and embedded applications. Third, the proposed research will use the biologically inspired and scalable cellular-automata-based coordination model to enable diffusion (epidemic) style information dissemination in ubicomp environments.