WebSplitter symbolizes the union of pervasive multi-device computing and collaborative multi-user computing. WebSplitter provides a unified XML framework that enables multi-device and multi-user Web browsing. WebSplitter splits a requested Web page and delivers the appropriate partial view of each page to each user, or more accurately to each user's set of devices. Multiple users can participate in the same browsing session, as in traditional conferencing groupware. Depending on the access privileges of the user to the different components of content on each page, WebSplitter generates a personalized partial view. WebSplitter further splits the partial view among the devices available to each user, e.g. laptop, wireless PDA, projection display, stereo speakers, orchestrating a composite presentation across the devices. A wireless PDA can browse while remotely controlling the multimedia capabilities of nearby devices. The architecture consists of an XML metadata policy file defining access privileges to XML tags on a Web page, a middleware proxy that splits XML Web content to create partial views, and a client-side component, e.g. applet, enabling user login and reception of pushed browsing data. Service discovery finds and registers proxies, browsing sessions, and device capabilities. We demonstrate the feasibility of splitting the different tags in an XML Web page to different end users' browsers, and of pushing updates from the browsing session to heterogeneous devices, including a laptop and a PDA.

This paper motivates and details a document-based framework for manipulating the components that comprise distributed Internet applications. In the framework, XML documents are used to describe both server-side functionality and the mapping between a client's applications and the servers it accesses. Our system model contrasts with explicitly context-aware application designs, where location information must be explicitly manipulated by the application to affect change; instead, a middleware layer is interposed between client applications and services so that invocations between the two can be transparently remapped. This approach is useful for a subset of application domains, including our example domain of "remote control" of local resources (e.g., lights, stereo components, etc.). We illustrate how the framework allows for 1) remapping of a portion of an existing user interface to a new service, 2) viewing of arbitrary subsets and combinations of the available functionality, and 3) ...

People often use a variety of computing devices, such as PCs, PDAs, and cell phones, to access the same information. The user interface to this information needs to be different for each device, due to the different input and output constraints of each device. Currently designers designing such multi-device user interfaces either have to design a UI separately for each device, which is time consuming, or use a program to automatically generate interfaces, which often result in interfaces that are awkward. Each method also discourages iterative design, considered critical for creating good user interfaces. We are creating a system called Damask to support the early-stage design of user interfaces targeted at multiple devices. With Damask, the designer will design a user interface for one device, by sketching the design and by specifying which design patterns the interface uses. The patterns will help Damask generate user interfaces optimized for the other devices targeted by the designer. The generated interfaces will be of sufficient quality so that it will be more convenient to use Damask than to design each of the other interfaces separately, and the ease with which designers will be able to create designs will encourage them to engage in iterative design. Damask will also

Everyday appliances, including telephones, ovens, and home stereos, increasingly contain embedded computers to provide greater functionality. Unfortunately, as these appliances become more complex, their interfaces are becoming harder to use. At the same time, more people than ever are carrying computerized devices that can communicate, such as cellular telephones, personal digital assistants, and even some watches. Our vision is that these devices will be able to communicate with our everyday appliances using a short-range wireless network, enabling people to control their appliances from a single handheld device. We present two studies that suggest that handheld devices could be used effectively as remote controls for everyday appliances. Keywords: Handheld computers, remote control, appliances, Personal Digital Assistants (PDAs), Palm, PocketPC, Pebbles

Pervasive computing offers the vision of seamless interaction by users with pervasive smart spaces filled with many wireless and wired devices, including monitors, speakers, printers, kiosks, soda machines, appliances, toys, sensors, and networked software services. To achieve seamless interaction, we must first address what we term as the active device resolution problem: when a user enters a smart room filled with N devices, which of the N devices is the "active device" that the user intends to interact with immediately? This paper focuses on the particular interaction mode introduced by remote control PDA's and cell phones. Manual selection of the intended device, either by pointing-and-clicking, gesturing or selecting a device from a software menu, is either imprecise or decidedly intrusive. Automated selection of the active device, using context clues and user history, is a step towards the vision of more seamless interaction. In this paper, we study the historical behavior of a small sample of users and apply various prediction algorithms to user history to automatically select the next active device that a user intends to interact with. We show that the accuracy of prediction can vary depending upon the algorithm, e.g. up to 90% using 3 order Markov prediction, and upon the length of training.

We have designed, implemented, and deployed a camera control system and a conference controller that provide remote control capabilities for videoconferencing over the Internet. The camera control system allows users to pan, tilt, and zoom the cameras, switch between cameras, and get a picture-in-picture view from their desktops. The conference controller allows conference participants to not only start and stop the media tools on a remote host, but also to dynamically change settings and turn transmission on and off. It supports the vic (video) and vat (audio) Internet videoconferencing tools and enhances their usability by providing an integrated and secure user interface for local and remote control of these applications. This paper describes the design and implementation of the camera control system (devserv and camclnt) and the conference controller (confcntlr). The remote control capabilities offered by these tools have changed the videoconferencing paradigm to one of telepresen...

Application sharing in teaching context with wireless networks Application sharing in teaching context with wireless networks

Pervasive computing offers a vision in which every room in the home and at work will become an interactive smart space filled with wireless and wired devices whose behavior can be remotely controlled by a user, including monitors, speakers, printers, kiosks, soda machines, appliances, toys, sensors, and networked software services. The goal of this paper is to address what we term the active device resolution problem in pervasive smart spaces. Given a user with a wireless PDA or cell phone who wishes to remotely control one of N devices or services within a smart room, which of the N devices is the intended or “active” device whose user interface (UI) should be automatically selected and prefetched before the user manipulates the remote control PDA? Automated selection of the UI eases the user’s interaction with a pervasive environment, in comparison to manual selection, which is cumbersome, and directional remote control, e.g. pointing and clicking, which is insufficient to resolve the active device ambiguity when a group of devices is closely spaced, as in a home entertainment system. Our goal is to anticipate the next user interface desired by the user based on each user’s history of remote control accesses. We present a study of various prediction algorithms applied to user behavior, including first and second order Markov prediction as well as naïve Bayesian prediction, and show that the accuracy of prediction can range from 75-90%, depending upon the algorithm and the degree of training.

Distributed multimedia applications typically handle two different types of communication: request/reply interaction for control information as well as real-time streaming data. The CORBA Audio/Video Streaming Service provides a promising framework for the efficient development of such applications. In this paper, we discuss the CORBA-based design and implementation of Campus TV, a distributed television studio architecture. We analyze the performance of our test application with respect to different configurations. We especially investigate interaction delays, i.e., the latencies that occur between issuing a CORBA request and receiving the first video frame corresponding to the new mode. Our analysis confirms that the interaction delay can be reasonably bounded for UDP and RTP. In order to provide results which are independent from coding schemes, we do not take into account any media specific compression issues. Hence, our results help to make essential design decisions while developing interactive multimedia applications in general, involving e.g., distributed synthetic image data, or augmented and virtual reality.

The use of multimedia in telematics and new services