Research Projects
The Mobile and Pervasive Computing Group's research revolves around software engineering issues related to mobile and pervasive computing. We are a member of UT's Center for Excellence in Distributed Global Environments (EDGE). Some information about our specific ongoing and completed research projects can be found on this page. Also see our Publications for up-to-date pending and published papers. An abbreviated list of projects can be found on our projects page.

Current Projects

  • Programming Abstractions for Ubiquitous Computing
    This project is developing programming abstractions and development tools that enable application developers to effeciently interact with ubiquitous and pervasive systems. Traditional pervasive systems are typically designed for a specific application and can afford tight coupling between applications and the deployment technologies of the application's evironment. These application-specific deployments will soon give way to more generic and flexible deployments which will support multiple applications developed by disjoint development teams. To support this transistion we must provide consistent programming interfaces and flexible support to application developers.

    At the heart of this project is the need to find the proper level of abstraction for ubiquitous environments, and developing programming metaphors that are appropriate. Currently, we are pursuing two lines of research in this area. The Application Sessions Middleware project unifies the tasks of resource discovery and connection maintenance into a single session. The Evolving Tuples project provides a generic platform which is deployed to nodes in a pervasive environment. The Evolving Tuples platform can be leveraged by new applications without requiring updates to the individual nodes, while still protecting them from attackers.

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  • DAIS: Declarative Applications in Immersive Environments: In this project, we are developing communication, coordination, and programming abstractions that allow a mobile application on a PDA to interact directly with resource-constrained sensors in the local environment to retrieve information on-demand without using a single network access point. The project includes novel abstractions for sensor data aggregation and fusion performed within the network on the resource constrained devices.
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  • Passive Context Sensing: Adaptation in pervasive computing required up-to-the-minute understanding of the state of the environment, which often comes with a significant added cost in terms of computation and communication. We are exploring possibilities for measuring environmental and network aspects using only passive sensing which incurs no additional communication overhead in the network. This context information can subsequently be used by a node to adapt communication and application protocols to current conditions.
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  • SMASH: Secure Mobile Agent Middleware: As software components become able to move among hosts in the network, a question arises in how to secure interactions between the agents and among the agents and their host platforms. SMASH investigates the variety of these security requirements, provides a mobile agent architecture that embodies them, and still allows agents to move and coordinate anonymously to a limited extent.
    Papers:
    • Pridgen, A. and Julien, C., "SMASH: Modular Security for Mobile Agents," In Software Engineering for Large-Scale Multi-Agent Systems V, Lecture Notes in Computer Science, 2007.
    • Pridgen, A. and Julien, C., "A Secure Modular Mobile Agent System," in Proceedings of the 5th International Workshop on Software Engineering for Large-Scale Multi-Agent Systems (SELMAS'2006) co-located with ICSE'06, Shanghai (China), May 2006.

  • Cross-Layer Discovery and Routing: This work addresses the need for application-adaptiev communication in mobile ad hoc networks that creates network routes based on applications' dynamic resource requests. We have introduced an intuitive generalization of source routing which facilitates discovery of a resource in a mobile ad hoc network and the creation and maintenance of a route from the requesting host to the discovered destination. We thus eliminate the requirement that existing routing protocols be coupled with a name or resource resolution protocol, instead favoring an entirely reactive approach to accommodate significant degrees of mobility and uncertainty.
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  • Sliverware for Collaborative Mobile Applications: Despite computers' widespread use for supporting personal applications, very few programming frameworks exist for creating synchronous collaborative applications. Enabling real-time collaboration demands lightweight, modular middleware that enables the fine-grained interactions requried by collaborative applications. We have introduced sliverware that provides extreme modularity and customizability while at the same time realizing our goal of simplifying cooperative application development.
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  • Middleware for Integrating RFID Systems: RFID solutions have become essential in monitoring inventory and in other large volume tracking and tagging applications. We are exploring this area on two fronts: first, how do we simplofy and enable on-demand access to RFID stored information through middleware, and, second, how can we integrate information sensed about the environment with identity information from RFID sensors to enable context- and identity-aware applications?

Past Projects

  • Network Abstractions: The network abstractions model provides a formal abstract characterization of an application's context that extends to encompass a neighborhood within the ad hoc network. The model includes a context specification mechanism that allows individual applications to tailor their operating contexts to their personalized needs. The associated communication protocol, source initiated context construction, or SICC, provides this context abstraction in ad hoc networks through continuous evaluation of the context. This relieves the application developer of the obligation of explicitly managing mobility and its implications on behavior.
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  • EgoSpaces: EgoSpaces is a coordination model and middleware for ad hoc mobile environments that focuses on the needs of application development in ad hoc environments by proposing an agent-centered notion of context, called a view, whose scope extends beyonr the local host to data and resources associated with hosts and agents within a subnet surrounding the agent of interest. An agent may operate over multiple views whose definitions may change over time. An agent uses declarative specifications to constrain the contents of each view by employing a rich set of constraints that take into consideration properties of the individual data items, the agents that own them, the hosts on which the agents reside, and the physical and logical topology of the ad hoc network. We have formalized the concept of view, explored the notion of programming against views, discussed possible implementation strategies for transparent context maintenance, and generated a protoype system.
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  • Context UNITY: Context-aware computing refers to a paradigm in which applications sense aspects of the environment and use this information to adjust their behavior in response to changing circumstances. We have created a formal model and notation (Context UNITY) for expressing quintessential aspects of context-aware computations; existential quantification, for instance, proves to be highly effective in capturing the notion of discovery in open systems. Furthermore, Context UNITY treats context in a manner that is relative to the specific needs of an individual applications and promotes an approach to context maintenance that is transparent to the application.
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