Wireless Infrared Networking in the Duke Paperless Classroom. (1995)

During the spring semesters of 1994 and 1995, freshmen in Duke University's Department of Biomedical Engineering participated in the first full-scale classroom test of diffuse infrared (IR) networking. experiment was known as The Duke Paperless Classroom and the subject of the course was introductory computer programming and numerical methods. Reported in numerous mainstream press publications (see sidebar), it's one example of cutting-edge learning environments afforded by new technologies. This article names the products used and reports on how classroom dynamics were (and were not) changed, and which instructional strategies proved most effective in this environment. project used an IR networking device from Photonics called the Cooperative Transceiver. A total of 72 student volunteers purchased Macintosh PowerBooks (Models 165c and 520, in the two successive years) and carried them into the classroom twice a week. IR devices were used to form a LocalTalk network in the classroom. teacher's PowerBook was attached to computer graphics projector (ViewFrame SpectraC) projected on a big screen in front of the class, replacing the chalkboard and traditional slide projectors. Farallon's Timbuktu Pro software was utilized as it allowed the teacher to project the screen of any student's computer over the IR network onto the big screen, and also to functionally take over and control that student's keyboard and trackball. teacher could, in effect, lean over any shoulder with the rest of the class watching. In addition, individual students could take turns operating the teacher's computer via Timbuktu as well, allowing the whole class to work together on joint projects using a single computer. No physical alteration was required to the classroom itself. * What is Diffuse Infrared Communications? Computer clusters on campus have been connected by networks for decades, but portable computers offer new challenges to networking technologies. Wireless communications provides distinct advantages here, including the ability to: * Provide local area networks without physically altering the classroom or limiting service to specific locations; and * Provide access to printers or the Internet for students within large public spaces such as the library or common room, while preserving local mobility within such spaces. Photonics device is the first commercially available embodiment of a new wireless technology based on diffuse infrared light.[1] device is about the size of a computer mouse and plugs into the back of a Mac PowerBook, from which it derives power. transceiver uses the same sensor and emitter elements found in television remote controls. However, unlike line-of-site devices which must be pointed at each other, the diffuse IR transceiver is sensitive enough to capture reflections from ceilings and walls. This permits a large number of transceivers in a typical lecture hall to be connected simply by pointing them at the same general area of the ceiling (we tested up to 41 at once). Unlike radio devices, there is no interference from neighboring rooms. speed of the present IR network between Mac PowerBooks is the same as that for wired LocalTalk connections, about 230 kilobits per second (kbps). In fact, the IR hardware is completely transparent to networking and printer software, including the software built into every Macintosh. Any two Macintosh computers equipped with infrared devices may share files peer-to-peer without additional software or set-up. A similar IR device, from Photonics, inserts into a PCMCIA slot of any IBM compatible, and runs at approximately 1 megabit per second (Mbps). These speeds are roughly 10-40 times slower than typical Ethernet, which operates at 10 Mbps. Nonetheless, diffuse IR is fast enough to support certain important in-classroom functions, in particular, screen sharing and remote control between the teacher and a single student. …