A Cooltown Demonstration at Mobicom 2000
Internet and Mobile System Labs
Hewlett Packard Laboratory
1501 Page Mill Road Palo Alto, CA
Contact: John J. Barton, John_Barton@hpl.hp.com

The HP Labs Cooltown project (www.cooltown.hp.com) demonstrates novel but realistic approaches to the support of mobile users in dynamic environments. We leverage web technologies to maintain "web presence" for people, places, and things. By accessing, manipulating, and communicating through these web representations of the physical world, people engage in "ad-hoc" or "emergent" applications where ever they may be located.

Things become web-present by embedding web-servers in them or by hosting their web-presence within a web server. Places become web present by organizing web things into collections under the management of a web-service we call a "PlaceManager". People become web present by offering global web home pages with "WebLink" services to facilitate communications and by offering information via location-specific PlaceManagers. Our work reflects a vision of integrating the physical and web worlds so people can enter new places and find the things they need easily.

Focus Area in Mobility.

Our work spans networks, applications, and interfaces. We combine existing networking technologies using existing interface standards but we add new infrastructural software to support communications-based applications. We are mostly concerned with new mobility usage patterns that leverage web ubiquity, new digital appliances, and advances in wireless networking.

Web ubiquity enables mobility in two ways. First, we will demonstrate how to deliver web services to mobile users without requiring a global wireless connection like a cell phone or mobile IP. The rising quality and reach of the Internet that supports the Web increases the probability of web-access in mobile venues. People use the Web at work and at home today; increasingly they will find it available when they shop or travel; eventually they will find adequate access "everywhere" they want electronic connections. Since the scope of services available or potentially available on the Web vastly exceeds the services available to closed mobile platforms, we believe web access will characterizes many successful mobile applications. However, this access can be intermittent and it can result from web-ubiquity rather than wide-area connectivity. .

Second, we will demonstrate ways mobile web clients can find and interact with web servers providing mobility services. Web ubiquity has created usable international standard communications protocol. Since most mobile venues will increasingly include web access, most mobile devices will have web software. This software will be able to interact with web services; that interaction will define mobile computing. To leverage this client software and communications system, we have invented new ways of integrating mobile devices and web-based support systems. In addition to web ubiquity, myriad new lightweight, less expensive, high function digital appliances obviously increase the potential for mobile systems. To integrate these devices with our increasingly powerful computer communications infrastructure remains a big challenge. In our view, these new devices are not and will not be patterned after workstation or desktop systems. Indeed the most interesting new devices for mobility include phones, watches, and cameras, not shrunken-screen mobile PCs. The diversity of these devices argues against software support based on device type or even application type. Rather we believe open web-based systems have proven the best at adapting to diversity. Our demonstrations will include a variety of digital devices.

Beyond web-ubiquity and new devices, wireless connectivity vastly improves the mobile user experience. Our demonstrations will show how infrared can be combined with 802.11 networking to achieve new application effects. While global wireless connectivity via phones or mobile Internet are important, our interest focuses on augmenting these technologies with short-range connectivity that allows mobile users to obtain location-specific information or applications.

A pervasive Web, a pile of neat devices, and some nifty wireless technology does not add up to a usable system. The Cooltown project seeks to fill in the missing pieces, to help transform these raw materials in the potent new tool it can be.

Technologies Involved in the Research.

Cooltown leverages the successful, open, ad-hoc architecture: the web. Web systems operate with request-reply document transfers not at the function call level; they communicate documents to achieve computations; they use simple ASCII encodings and are highly layered from IP up to XML. As much as possible we adapt these characteristics to mobile applications support.

Specifically we use Uniform Resource Locators (URLs) for addressing, providing both usability and flexibility. People, places, and things are all represented via URLs: at first contact all objects are web services. Consequently we have no API or "driver" model beyond the transfer of data between clients and servers. While subsequent communication can establish alternative relationships, a great deal can be done within the web communications model.

We have multiple approaches to service discovery, including infrared beaconing of URLs, bar code, RFID, and iButton mapping to URLs, and IP network multicast discovery. Our directory systems are just web pages from web servers or directories encapsulated behind web query forms. Notably our directory for a "web place" is actively managed to support mobile users and dynamic places. A place can be discovered by, for example, infrared beacons and it can contain services local to the physical area near the beacon. Thus our web-place is not confined to a specific network topology: it represents the services associated with a physical place, not the services associated with how the building happened to be wired.

Vital to the success of our scenarios is our use of URLs in handheld devices. A wide variety of handheld devices could support a "clipboard" function for URLs. We show how this simple facility can be combined with location-dependent physical addresses (like beacons and tags) and web-aware appliances to support mobile users. On top of the basic infrastructure we have built a number of example applications, including support for a Cooltown conference room, a bus for travelers in Cooltown, a Cooltown museum and bookstore, and a Cooltown cafe. Each example illustrates some aspects of the Cooltown vision.

Technical and Equipment Requirements.

LAN speed Internet access would make our demo more convincing.

Demo Layout and Space Requirements.

Our demo will consist of 5 stations each 4'x4' with at least one side to the visitors and one side shared with another station.

Interoperability.

We can provide software for conference attendees using Palm or WinCE devices who want to try the demos with their own equipment.