Physicalnet: A Generic Framework for Managing and Programming Across Pervasive Computing Networks

Abstract

This paper describes the design and implementation of a pervasive computing framework, named Physicalnet. Essentially, Physicalnet is a generic paradigm for managing and programming world-wide distributed heterogeneous sensor and actuator resources in a multi-user and multi-network environment. Using a four-tier light-weight service oriented architecture, Physicalnet enables global uniform access to heterogeneous resources and decouples applications from particular resources, locations and networks. Through a negotiator module, it allows a large number of applications to concurrently execute on the same resources and to span multiple physical networks and logical administrative domains. By providing a fine-grained usebased access rights control and conflict resolution mechanism, Physicalnet not only ensures owners having total control of sharing and protecting their resources, but also dramatically increases the number of applications that can concurrently execute on the devices. Furthermore, Physicalnet supports resource dynamic location-aware mobility, application run-time reconfigurability and on-the-fly access rights specification. To quantify the performance, we evaluate Physicalnet based on memory usage, the number of concurrent applications, and dynamic responsiveness. The results show Physicalnet has excellent performance, but low overheads.

Bundle: A Group-Based Programming Abstraction for Cyber-Physical Systems

“…The Bundle is designed as part of Physicalnet [17], a lightweight service oriented architecture middleware for wireless sensor networks. Detailed description and evaluation of Physcialnet are provided in [17].…”

“…Detailed description and evaluation of Physcialnet are provided in [17]. Here, we briefly outline the implementation of Physicalnet only at the level of detailed required to understand the implementation support for Bundles.…”

“…Note that, multiple applications can use the same service provider and have conflicting requirements (e.g., one application may want the light to be on and other to be off). In that case Physicalnet uses conflict resolution mechanisms that are discussed in detail in [17]. The providers are free to move from one remote WSN to another.…”

“…Note that the Bundle abstraction is implemented on top of the Physicalnet middleware [17]. While the Bundle is an important part of the Physicalnet framework, it is an orthogonal concept.…”

“…In this current paper, we fully describe the Bundle as a group based abstraction, discuss how it is different from existing group based abstractions, and evaluate its conciseness and energy consumption. A previous paper ( [17]) discusses the features of Physicalnet including the detailed description of its middleware architecture, its access right control mechanism, how it is different from other existing middleware, and an evaluation of its performance and concurrency degree. So these two papers are fundamentally different with minimal overlap.…”