ETH Zurich : Computer Science : Pervasive Computing : Distributed Systems : Education : Student Projects : Abstract

A Smart Gateway Infrastructure for the Web of Things (M)

Status: Abgeschlossen

Recently the Web experiences a new breath and is evolving from serving and connecting virtual documents together to connecting and serving “things”. Within the Web of Things [1,2,3] project we explore the use of web patterns (e.g. REST, Atom, etc.) to integrate sensors, actuators, embedded computers and tagged real-world objects to the web. Thus, smart things can then be browsed for, bookmarked, indexed and searched for.

To make smart things part of the Web, two solutions are possible: direct Web connectivity on the devices or through a proxy. Previous work has shown that embedded Web servers on resource constrained devices is feasible and it is likely that in the near future most embedded platforms will have native support for TCP/IP connectivity (in particular with 6LowPAN), therefore a Web server on each device is a reasonable assumption. This approach is sometimes desirable because there is no need to translate HTTP requests from Web clients into the appropriate protocol for the different devices, thus devices can be directly integrated and make their (RESTful) APIs directly accessible on the Web.

However, when an on-board HTTP server is not possible or not desirable, Web integration takes place using a reverse proxy that bridges devices that do not talk IP with the Web. We call such as proxy a Smart Gateway to encapsulate the fact that it is a network component that does more than only data forwarding. A Smart Gateway is actually a Web server that abstracts behind a RESTful API the actual communication between devices and the gateway (e.g.. Bluetooth or Zigbee) through the use of dedicated drivers. From the Web clients’ perspective, the actual Web-enabling process is fully transparent, as interactions are HTTP in both cases.

Building upon previous projects [4,3], the main goal of this thesis is to implement a modular Smart Gateway system for the Web of Things (using OSGi). In particular, it consists of three parts:

• Web-Enabling Devices: Evaluate, implement and compare approaches to the RESTful integration of devices into the Web of Things. The evaluation should also include REST-enabling several real-world devices.
• Infrastructure for Smart Gateways: Develop and evaluate a Smart Gateways infrastructure that provides services on top of the integration of devices into the Web of Things, in particular the ability to efficiently search for services provided by different, web-enabled, devices.
• Integration of the smart things with different Web 2.0 applications and plateforms (e.g. Twitter, XMPP) via the Smart Gateways to foster interactivity and information sharinge. This should also foster physical-virtual mashups involving real-world devices and existing services on the Web.

References:

[1] Guinard, Dominique, and Vlad Trifa. “Towards the Web of Things: Web Mashups for Embedded Devices.” In Workshop on Mashups, Enterprise Mashups and Lightweight Composition on the Web (MEM 2009), in proceedings of WWW (International World Wide Web Conferences). Madrid, Spain, 2009.

[2] Erik Wilde. „Putting Things to REST“, UCB iSchool Report 2007-015, School of Information, UC Berkeley, 2007.

[3] Dominique Guinard, Vlad Trifa, Thomas Pham and Olivier Liechti. “Towards Physical Mashups in the Web of Things.” In International Conference on Networked Sensing Systems, INSS 2009.

[4] Vlad Trifa, Samuel Wieland, Dominique Guinard, Thomas Michael Bohnert "Design and Implementation of a Gateway for Web-based Interaction and Management of Embedded Devices." Proceedings of the 2nd International Workshop on Sensor Network Engineering (IWSNE 09). Marina del Rey, CA, USA, June 2009