Distance Education Using Linux and the MBone
North Carolina State University has been running MBone classes since the fall of 1996. In this time, a number of undergraduate engineering courses have been delivered to participating universities and community colleges. At NC State, a classroom was constructed specifically for distance education (see Figure 5). This classroom contains seating for local students. There are two remote-control video cameras, one for the lecturer and one for the students. There are three large television monitors on which the computer screen is shown to the local students. There is a control area with a computer workstation, document camera, two small TV monitors and an AMX controller. The AMX controller controls the cameras as well as the other audio and video sources. It also provides a central control to operate the other equipment in the room. The most innovative feature of the classroom is a digital projection SMARTBoard mounted on the front wall of the classroom. The SMARTBoard is an input device manufactured by SMART Technologies. It is essentially a touch-sensitive version of a standard office whiteboard. Whatever is written on the surface of the SMARTBoard is transmitted to the computer. The projection version used in the classroom works in combination with an LCD projector to project an image of the computer screen directly onto the SMARTBoard. In this way, the lecturer essentially writes directly on the computer screen. The SMARTBoard is large enough that the local students see directly what the lecturer is writing on the SMARTBoard. This technology provides a natural closed-loop interface to the computer that closely parallels the traditional classroom blackboard.
Generally, a teaching assistant operates the computer equipment and cameras while the instructor lectures. This frees the instructor from having to deal with any technical issues while the class is in session. One of these issues relates to the floor-control aspect of DETA. The floor-control provided by the Electronic Hand Raiser is purely voluntary, and requires all participants to follow the correct protocol. Often we have found that remote participants will scribble onto the shared whiteboard to get the lecturer's attention, or the instructor will simply fail to acknowledge incoming questions. A good solution to the floor-control issue remains to be found and usually it is the assistant's responsibility to help the lecturer acknowledge any questions. Another associated issue occurs when a local student asks a question. The lecturer must repeat the question in order for it to be heard by the remote sites. Often the lecturer will mysteriously stop speaking for a moment, and then start answering a question that none of the remote participants ever heard asked. Remote participants are then forced to either figure out what had been asked, or interrupt the flow of class and ask the lecturer what the original question was. One solution to this problem has been to give students their own microphones. Unfortunately, this relies either on them remembering to activate the microphone, or on distracting continuous presence audio.
The overall response by students to the MBone classes has been positive. The interactive capabilities provided by the MBone tools are far superior to videotapes or broadcasts. They provide a richer educational experience, more similar to a traditional classroom. Most instructors have been able to adapt well to the technology, though there exists somewhat of a learning curve for those accustomed to traditional classroom teaching. One of our primary aims in the future is to flatten this learning curve and make the technology more transparent to the user. Ideally, an instructor should be able to walk into a classroom, activate the equipment, and begin lecturing immediately, without giving any more thought to the underlying technology. While this goal has yet to be achieved, we feel that the MBone tools and DETA, in combination with the Linux platform, represent a highly usable and cost-effective vehicle for the delivery of interactive distance education. For more information, as well as links to all of the DETA and MBone software, visit our web site at http://www.engr.ncsu.edu/deta/.