A lightweight resource-oriented application framework for wireless sensor networks
Andreas Kamilaris · Repository for Publications and Research Data (ETH Zurich) · 2009
With current advancements in technology, an increasing number of embedded devices are being deployed around the world to solve dedicated, specific tasks like environmental monitoring or automating control.These resource-constrained devices operate in specialized, low-level physical links.We investigate the use of smart gateways to provide access on the Internet for these devices.These gateways are responsible for discovering heterogeneous sensor devices in their neighborhood, extracting automatically as much information as possible concerning their characteristics and functionality and making them available as Web resources that can be accessed in an uniform way, independently of their low-level specific characteristics or the different communication protocols they use.We also examine ways of accelerating performance and augmenting functionality of these resource-constrained devices in order to solve traditional problems that always exist in the unpredictable environment of sensor networks and concern energy constraints, reliability issues, transmission conflicts and device failures.Our gateway links physical devices with existing Web technology, bringing sensor technology one step further, towards the way of full integration with the Web, in order to enable the vision of the Web of Things.After these theoretical issues, we begin explaining the practical stuff.In Section 6, an overall view of the gateway as we designed and implemented is available and in Section 7 the RESTful software for resource-constrained devices we developed is presented.Then we continue with an evaluation of our model in Section 8, where we describe a number of experiments we prepared in order to test the performance of our system.Last, in Section 9 some conclusions are extracted generally about the paper and some future work that would enhance the functionality of our gateway is listed. ContributionOur gateway model, offers an efficient approach for solving the problem of Web-enabling heterogeneous, embedded devices.Interaction patterns, based on REST architectural principles, provide uniformity and interoperability in a high-level, proposing solutions to challenges such as device discovery and service description.Through its unique design, our gateway is transformed into an application framework where powerful, flexible applications can be developed with little effort and where multi-user concurrency is provided.The mechanisms we integrated in gateway's structure, mask away failure issues and transmision conflicts, providing robustness, reliability and advanced performance.Hence, an application programmer does not have to worry about these issues.These "smart" gateways, by design, are capable of creating in the future a backbone structure for the Web of Things.