Foreword: In this whitepaper, Hewlett-Packard Labs researcher Wesley Chan introduces the embedded Linux community to the innovative R&D activities taking place within HP's “Cooltown” program. Chan defines the initiative's philosophy and goals, describes several key open source software and hardware components that have been developed, and explains how developers and companies can join in… creating the Cooltown vision of a world in which “humans are mobile, devices and services are federated and context-aware, and everything has a web presence.”

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Do more by doing less

A quarter century ago, computer visionary Alan Newell gave a talk in which he saw an “enchanted world” where “instruments would converse with their users” and “streetlights care about those who walk under them, so no one gets lost.” Back then, such visions were no more than a fairy tale; it was a far-off place that people only imagined.

Newell's enchanted world, however, is now closer than ever. As part of HP's Cooltown program, created at HP Labs, we've built museum exhibits that engage and talk to you, conference rooms that automatically recognize and reserve the room for you if you haven't done so already, and even radios that know and automatically play back your favorite songs when you walk into the room.

Building smart devices and intelligent ecosystems

The Cooltown program explores how to build smart devices and connected ecosystems. During the last four years we've explored prototypes from smart, networked printers to intelligent living rooms, and all have challenged us in several ways.

First, a wide variety of different devices and ways of connecting them exist. If you look at PDAs alone, you might be carrying a Pocket PC, while the person sitting next to you may be using a Palm-based digital assistant. And the diversity of mobile phones can be daunting.

Second, we couldn't find a common architecture to manage the relationships between people, places, and things (devices). Creating an intelligent conference room meant that we would have to implement costly point solutions for each device, as well as custom data structures to represent your preferences to each device. In order to “transmit” your preferences to each device, we would additionally need a custom solution-a proprietary RMI mechanism, for example, or some variant of data serialization.

Enabling web interactions with the CoolBase platform

HP's CoolBase platform addresses some of the challenges associated with building both smart devices and intelligent ecosystems.

At the heart of the platform is the concept that everything has a web presence. A web presence is a collection of services and information that can be accessed through the web. It can be as simple as the home page for a user, or as complex as a directory of applications, services, and relationships encapsulated in an XML document.

CoolBase implements an architecture that links web presences with people, places, and things. The architecture is based on widely used web standards-HTML and XML over HTTP. This ensures that the CoolBase is open, extensible, and can interface with other web-based systems and services.

The platform consists of several software and hardware modules. These modules provide the tools needed to build ecosystems that enable users to interact with a wide variety of services on an even larger selection of “smart” devices. Some of the components of the CoolBase platform include . . .

• Esquirt — This module provides an application programming interface that encapsulates a device interaction model that enables smart devices to access the web presences of other devices and physical entities by reference. For example, Esquirt (pronounced “e-squirt”) enables a mobile phone to send (or “squirt”) the reference (e.g., a URL) of a document to a nearby printer. When the printer receives the reference, it retrieves the document and prints it for the user. Likewise, Esquirt also enables the mobile phone to act as a “universal remote control” for a wide variety of smart devices. When the phone connects to an Internet radio, for example, it retrieves a reference and subsequently displays the device's web presence on the screen. A person can operate the radio using the reflected user interface displayed on the phone.

• Web Presence Manager (WPM) — This module facilitates the creation and hosting of web presences for people, places, and things. Additionally, the WPM manages the contextual relationships between various web presences. For example, a conference room, a computer projector, and a printer may each have its own web presence. But if both devices are located in the conference room, the WPM can generate a relationship where the web presence of the conference room encapsulates the web presences of both devices.

  

• Cooltown Beacon and Taggy — The “Beacon” is a small, battery-powered hardware device that broadcast references (e.g., URLs) in specific locations. Beacons are used at HP Labs to broadcast a conference room's web presence to nearby PDAs and cell phones. The “Taggy” (see photo on right) is a small personal device (about the size of a key chain ornament that can store references acquired from one or more beacons or another Taggy. Additionally, a Taggy can broadcast (or “squirt”) references when a user activates the squirt mode. Both beacon and Taggy device designs are currently implemented using infrared communications, but could be redesigned to support wireless radio networking as well.

• CoolBase Appliance Server — This module is a simple web application server designed specifically for use in embedded systems — like printers and computer projectors. The module consists of an embedded web server that can host web services and serve dynamically generated web pages. The appliance server is especially useful in creating and hosting web presences directly on embedded devices.

Putting Everything Together

At HP Labs, we've used CoolBase to prototype several compelling applications. We've prototyped an Internet Radio that can be controlled from any web-enabled device-including a PDA, cell phone, or even your PC. We also used beacons and our Esquirt software loaded on HP personal digital assistants to create a virtual tour guide for the Exploratorium, a science museum in San Francisco, California. We used Web Presence Manager to create and host online information and interactive games for each of the different exhibits.

CoolBase allows you to easily create devices and ecosystems that “do more by doing less,” as an MIT computer science professor put it. The CoolBase appliance server enables you to prototype smart devices quickly. The Web Presence Manager, Esquirt, and the beacon modules provide a useful way to build smart environments and intelligent ecosystems. Taken together, CoolBase is our effort to bring us closer to that “enchanted world” that Newell speaks of — one that no longer seems so far away.

The CoolBase Platform can be downloaded from HP's Cooltown Developer's Network website, and is open-sourced under the GNU Public License (GPL).

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About the author: Wesley Chan is currently a Cooltown researcher at Hewlett-Packard Laboratories. He recently received his Masters Degree at MIT, where he spent most of his time at the Media Laboratory hacking digital cameras and figuring out how to bring the Internet into your supermarket (info here). When he's not trying to connect his cell phone to his washing machine, Wesley enjoys snapping tons of photos while hiking or SCUBA diving.

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This article was originally published on LinuxDevices.com and has been donated to the open source community by QuinStreet Inc. Please visit LinuxToday.com for up-to-date news and articles about Linux and open source.