Building a Scalable and Open World Wide
Web of Things
University of Lugano
26 March 2009
Vlad Trifa and Dominique Guinard

Outline
‣ Introduction
‣ Web of Things
‣ REST on devices
‣ Gateways
‣ Goodies
Thursday, March 26, 2009 Vlad Trifa - SAP/ETH Zurich - www.webofthings.com

From barcodes...
‣ Growing trend to connect
physical objects to the Web
‣ Barcodes do that well
Thursday, March 26, 2009 Vlad Trifa - SAP/ETH Zurich - www.webofthings.com

To RFID tags...
‣ With RFID tags more
things are possible
‣ Each object has an ID
‣ Read at a distance
‣ New interaction modes
‣ ...
Image courtesy of Timo Arnall - http://www.elasticspaces.com
Thursday, March 26, 2009 Vlad Trifa - SAP/ETH Zurich - www.webofthings.com

To microprocessors...
‣ Web connectivity: cheap &
ubiquitous
‣ Emergence of the physical Web
‣ Beyond Websites and browsers
‣ Soon more devices than humans
‣ And real-time Web
‣ RSS/ATOM, Twitter, etc..
Thursday, March 26, 2009 Vlad Trifa - SAP/ETH Zurich - www.webofthings.com

The Challenge
How to integrate such a wide range of devices as
part of distributed applications (without a PhD in Computer science)?
‣ Devices with different capabilities/functions
‣ Tons of networking protocols
‣ Many incompatible applications/middlewares
‣ Proprietary solutions are rigid and difficult to customize
‣ Need for a common ground for devices!
‣ Maximizes interoperability, scalability, and evolvability
‣ Emphasizes reuse and sharing
‣ Easy to use
‣ Flexible
Thursday, March 26, 2009 Vlad Trifa - SAP/ETH Zurich - www.webofthings.com

Sounds very much like the Web...
Reuse the Web standards to develop
applications for networked objects.
‣ Web makes applications cheaper to develop
‣ 1.5 billion people use it and it is simple
‣ It is scalable, loosely-coupled, and evolvable
‣ Integrate and share real-time device data
‣ Devices and their properties become browsable
‣ Web becomes a collection of devices that can be
recombined at runtime to build applications
Thursday, March 26, 2009 Vlad Trifa - SAP/ETH Zurich - www.webofthings.com

REpresentational State Transfer (REST)
‣ Architectural style behind
the Web (NOT a standard)
HTTP CRUD
‣ Information unit is a
POST Create
resource identified by URI
GET Read
‣ Uniform interface
PUT Update
‣ Self-described messages
(MIME types) DELETE Delete
‣ Stateless
Thursday, March 26, 2009 Vlad Trifa - SAP/ETH Zurich - www.webofthings.com

REST on devices
‣ Devices and their properties are RESTful resources
GET device/sensors/temperature
POST device/sensor/LED
‣ Three possibilities to do that
‣ Full REST (HTTP) - Ideally!!
‣ Full customized solution with a gateway
‣ A mix of both
‣ But most devices can’t always have full REST...
‣ Low-power
‣ No HTTP or no IP support
‣ Proprietary protocols or API
Thursday, March 26, 2009 Vlad Trifa - SAP/ETH Zurich - www.webofthings.com

Gateways
‣ Enable RESTful access to
devices
‣ Any computer that runs Java
(NAS, routers, etc...)
‣ Fully Web compliant
Thursday, March 26, 2009 Vlad Trifa - SAP/ETH Zurich - www.webofthings.com

Smart Gateways
‣ Augment functionality (& perf) of devices and
leverage all what is available for the Web
‣ Not just a Web page/interface for device data
‣ Layering
‣ Caching of data
‣ Failure masking
‣ Complex functionalities not feasible on devices
‣ Complex decision processes
‣ Energy consumption optimization
‣ Localized access control and security
Thursday, March 26, 2009 Vlad Trifa - SAP/ETH Zurich - www.webofthings.com

Thursday, March 26, 2009 Vlad Trifa - SAP/ETH Zurich - www.webofthings.com

Thursday, March 26, 2009 Vlad Trifa - SAP/ETH Zurich - www.webofthings.com

Thursday, March 26, 2009 Vlad Trifa - SAP/ETH Zurich - www.webofthings.com

Thursday, March 26, 2009 Vlad Trifa - SAP/ETH Zurich - www.webofthings.com

Thanks!!!!!
www.webofthings.com
Thursday, March 26, 2009 Vlad Trifa - SAP/ETH Zurich - www.webofthings.com