Browsing by Author "Plymale, William O."

Now showing 1 - 3 of 3
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    Enhancing Input/Output Correctness, Protection, Performance, and Scalability for Process Control Platforms
    Burrow, Ryan David (Virginia Tech, 2019-06-07)
    Most modern control systems use digital controllers to ensure safe operation. We modify the traditional digital control system architecture to integrate a new component known as a trusted input/output processor (TIOP). TIOP interface to the inputs (sensors) and outputs (actuators) of the system through existing communication protocols. The TIOP also interface to the application processor (AP) through a simple message passing protocol. This removes any direct input/output (I/O) interaction from taking place in the AP. By isolating this interaction from the AP, system resilience against malware is increased by enabling the ability to insert run-time monitors to ensure correct operation within provided safe limits. These run-time monitors can be located in either the TIOP(s) or in independent hardware. Furthermore, monitors have the ability to override commands from the AP should those commands seek to violate the safety requirements of the system. By isolating I/O interaction, formal methods can be applied to verify TIOP functionality, ensuring correct adherence to the rules of operation. Additionally, removing sequential I/O interaction in the AP allows multiple I/O operations to run concurrently. This reduces I/O latency which is desirable in many control systems with large numbers of sensors and actuators. Finally, by utilizing a hierarchical arrangement of TIOP, scalable growth is efficiently supported. We demonstrate this on a Xilinx Zynq-7000 programmable system-on-chip device.
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    Pebbles and Urns: A Tangible, Presence-Based Service Delivery Framework
    Plymale, William O. (Virginia Tech, 2013-01-11)
    Wireless and pervasive computing research continues to study ways the Internet of Things (IoT)
    can make lives easier and more productive. Areas of interest include advances in new
    architectures and frameworks that support large-scale IoT deployments beyond research
    prototypes, simple and inexpensive human-to-device and device-to-device interfaces, and user
    decision making support with opportunistic information services.

    This dissertation investigates the design and implementation of a general-purpose framework
    upon which IoT and opportunistic computing (OC) systems can be built.

    The result of this work is Pebbles and Urns (P&U), a casually accessible system designed to
    deliver information to a person that is pertinent and beneficial to them with respect to their
    current activity, location and other contexts. P&U is a proximity-based information delivery
    framework that leverages a simple, inexpensive tangible interface and context-rich, physicallysituated,
    distributed information repositories. By its proposed use of enforced proximity, local
    context, and location-specific services, P&U can support the situated interaction between user
    and place.

    The P&U framework is based on a layered architecture consisting of an isolated physical
    communication layer, a data repository supporting opportunistic service composition and
    delivery, and a controller/interface providing user feedback. Serving as a potential IoT design
    pattern, P&U application developers can use the framework API\'s and software tools to build
    and deploy P&U systems.

    As validation of this work, P&U prototypes are constructed using the framework, API\'s and
    software tools. The prototypes are based on use cases depicting a person engaged in the day-today
    activities of attending class, going to the gym and grocery shopping. Performance
    measurements are performed on the prototypes profiling core components of the framework.
    Results indicate proper functioning of P&U tangible interfaces, communication connections,
    service request and delivery, and internal framework operations.

    Contributions of this research include a general-purpose framework, a simple IoT interface and
    an opportunistic engine.
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    Simulating IoT Frameworks and Devices in the Smart Home
    Kalin, John Howard (Virginia Tech, 2017-08-29)
    The rapid growth of the Internet of Things (IoT) has led to a situation where individual manufacturers develop their own communication protocols and frameworks that are often incompatible with other systems. Part of this is due to the use of incompatible communication hardware, and part is due to the entrenched proprietary systems. This has created a heterogeneous communication landscape, where it is difficult for devices to coordinate their efforts. To remedy this, a number of IoT Frameworks have been proposed to provide a common interface between IoT devices. There are many approaches to common frameworks, each with their strengths and weaknesses, but there is no clear winner among them. This thesis presents a virtual network testbed for implementing smart home IoT Frameworks. It consists of a simulated home network made up of multiple Virtual Machines (VM), simulated smart home devices and an implementation of the OpenHAB framework to integrate the devices. Simulated devices are designed to be network- accurate representations of actual devices, a LIFX smart lightbulb was developed and an existing Nest thermostat simulation was integrated. The demonstrated setup serves as a proof of concept for the idea of a home network testbed. Such a testbed could allow for the development of new IoT frameworks or the comparison of existing ones, and it could also serve as an education aid to illustrate how smart home IoT devices communicate with one another.