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In the fall semester of 1999, the University of Wisconsin in the United States, KEIO University in Japan, and NARA Institute of Science and Technology in Japan jointly developed a graduate school course called Introduction to Computer Networks using next-generation Internet technology and class archiving technology. This paper describes how this course was created, what kind of technology was used, and how all the participants (professors, students, staff, and faculty members) felt about the course. Then this paper discusses how the digital infrastructure will affect the university's role.
The basic requirements for the course design are as follows:
To achieve requirement 3, Professor Muari and Professor Hideki Sunahara from NAIST created new courses with their own exams but also including lectures from WISC.
There were challenges to achieving this objective, including the time difference, the school term schedule difference, and the course policy difference. Wisconsin and Japan are 15 hours apart (14 hours during daylight savings time). And the school term starts at the beginning of September and lasts for 10 weeks at WISC, starts at the end of September and lasts for 15 weeks at KEIO, and starts at the beginning of October and lasts for 10 weeks at NAIST. Therefore, there is no possibility for the three universities to have a single class scheduled at the same time.
As a result, three courses were set up:
In order to solve the time and schedule differences, we recorded all the WISC lectures and archived them online so that Japanese students could hear all the WISC lectures.
To achieve requirement 2, Professor Murai scheduled five lectures for students in the regular WISC class on the topics of wireless, multicast, Domain Name System (DNS), IPv6, and technical overview of this distance learning project.
WISC's course consists of six major topics: overview, link layer, network layer, transport layer, IP layer, and congestion control. To give Japanese students the opportunity to have an interactive session with him, Professor Landweber scheduled six lectures on these topics for KEIO and NAIST students during KEIO's regular class time.
As a result, KEIO students hear six interactive lectures from Professor Landweber remotely on six topics, seven lectures from Professor Murai locally (these explain the topics in a little more detail), and archived lectures for their homework. In addition, all these lectures by Professor Murai and Professor Landweber are archived online so that students at all other sites can hear those lectures anytime. NAIST students hear all the archived lectures at the class time and six optional interactive lectures from Professor Landweber remotely. WISC students hear 24 lectures from Professor Landweber locally and 5 lectures from Professor Murai remotely. All students are also welcome to participate in any of the special interactive sessions.
Based on the course design, we have 6 remote lectures involves 3 points, 5 remote lectures involves 2 points (WISC and KEIO), and about 45 archived lectures. The requirements for the systems are:
Interactive lectures over the Internet
Archived lectures on the Internet
For the interactive lectures, DVTS[1] is selected because of the following reasons:
DVTS, developed by the WIDE project and KEIO University, is a PC-based digital video data transport system. Two pairs of regular PCs (OS: FreeBSD) give bidirectional digital video (DV) quality conferencing (Figure 1). As DVTS transmits the DV data over the IP without any compression, the quality is very good and the delay brief, which is very important for interactivity. Also, DVTS can adjust the bandwidth usage based on the network condition from 40Mbps down to 10Mbps, which is important for all applications running on the Internet where the fixed bandwidth cannot be guaranteed. When DVTS reduces the transmitting data, it only reduces the video packets; audio quality can be preserved, which is also very important for lengthy lectures.
Figure 1. DVTS system overview
In order to minimize the international data transmission, the following system configuration is proposed (Figure 2). Video/audio from NAIST will be transmitted to KEIO, then transmitted to WISC analogically (e.g., side by side, picture in picture, or just switched) mixed with KEIO classroom video/audio. This way, only one stream runs on the international link. In Figure 2, stream a includes both KEIO and NAIST.
Figure 2. Communication among three points
We have two choices here on how to transfer b and c to both sites: (1) use IP multicast, or (2) use the cell copy feature of ATM switch. In this project, we started with the cell copy solution, then planned to transit to the multicast for future flexibility. But actually cell copy was used only for lectures and multicast was used only for testing. Figure 3 is the network configuration among the three points using the cell copy solution.
Figure 3. Network configuration
Interactive lectures are carried out by using IPv6 over the very high speed Internet test bed developed and operated by the joint effort among US-Internet2, APAN (Asian Pacific Advanced Network Association), JGN (Japan GIGABIT Network), JB (Japan Research and Development Network Association), and the WIDE project. For IPv6, KAME[2] implementation developed by WIDE project is used.
In order for two sites' students to see the same page of materials as the lecturer, we developed an application to synchronize the multipoint PowerPoint page over the Internet. This application works as follows:
Then, the page will be displayed on the listeners' screen and changed when the lecturer changes the page. Mouse events and page change events are transferred from the lecture system to the multipoint listener systems by using Internet Relay Chat (IRC) protocol. The RTP system runs on Windows 98 and is publicly available.
During the lectures and preparation, staff members communicate by IRC over IPv4. An IPv4 tunnel over IPv6 is prepared to serve IPv4 connectivity for the WISC classroom. KEIO and NAIST have IPv4 connectivity separate from IPv6 connectivity for DVTS.
For archiving lectures, the School of Internet (SOI) lecture archive system is used.[3] This system was developed by the WIDE project SOI working group and has been used since 1997. This system gives audio and video synchronized with materials using RealVideo and SMIL features (Figure 4). In order to support home users, video and audio is encoded under 64 kilobits per second (Kbps). Archived lectures are stored at the SOI site[4] and viewed by a wide range of users.
Figure 4. Archived lecture
All three classrooms are regular rooms, not rooms specially equipped for distance learning. Screens, projectors, and cameras are placed to meet the following requirements:
Figure 5 shows the classroom layout at KEIO. The other two sites are equipped similarly. In addition to the main screen (screen1), which displays the remote lecturer and screen 2 for material pages, 2 screens are placed to allow the lecturer to see students at the two other sites behind the local students. The camera that focuses on the lecturer's face is placed next to screens 3 and 4 to meet the eye-contact requirement. Another camera focuses on students and is used for question and answer sessions.
Figure 5. Classroom layout at KEIO
Figure 6 shows the equipment and staff layout. The blue line represents the video, the green line is audio, the orange line is audio and video, the black line is the PC and network facility, and the red line is the DV streams. A to G are the staff members. Table 1 explains their tasks.
Figure 5. System configuration and staff layout
| Position | Tasks | What to do |
|---|---|---|
| A | PC | Handle PC, DVTS, network operation |
| B | A/V to WISC | Mix and select the video and audio to send WISC |
| C | A/V at classroom | Select the video and audio to display the main screen and speaker for the classroom |
| D | Camera for students | Take video of students. |
| E | Camera for lecturer | Take video of local lecturer |
| F | Lecture recording | Record the audio/video for lecture archive. |
| G | Material | Display materials on screen 2 using RPT |
The handling of audio and video in the classroom, the video to send to WISC, and the video to record for the archives depends on the situation. Table 2 provides some explanation.
| Situation | Send from KEIO | KEIO Classroom | Recording for Archive | |||
|---|---|---|---|---|---|---|
| Video | Audio | Video | Audio | Video | Audio | |
| Lecture from WISC | KEIO (camera 2)/NAIST | -- | WISC | WISC | WISC | WISC |
| Lecture from KEIO | KEIO (camera 1) | KEIO | WISC | KEIO | KEIO (camera 1) | KEIO |
| Question and answer (Q&A) session between WISC students and KEIO professor | KEIO (camera 1) | KEIO | WISC | KEIO + WISC | KEIO (classroom camera) | KEIO + WISC |
| Q&A session between WISC lecturer and KEIO students | KEIO (camera 2) | KEIO | WISC | KEIO + WISC | KEIO (classroom camera) | KEIO + WISC |
| Q&A session from NAIST | NAIST | NAIST | NAIST | NAIST + WISC | KEIO (classroom camera) | NAIST + WISC |
Staff members are trained before the lecture term begins.
We carried out seven interactive sessions at three locations for lectures by Professor Landweber from WISC and five interactive sessions at two locations for lectures by Professor Murai from KEIO. Attending the interactive sessions were about 20 students from KEIO, 50 students from WISC, and 10 students from NAIST. Every time, WISC students asked questions of Professor Murai and Japanese students asked one or two questions of Professor Landweber. We concluded that the system achieved enough interactivity among the locations. The DVTS system did not work for one lecture due to IEEE1394 board unstability. On that day, Professor Murai gave a local lecture instead. Stability is the future issue. About six staff members are required to operate the equipment for each lecture. We need to find a way to automate and minimize the human resources. About 45 lectures were archived online and accessed by students inside and outside of those three universities (Figure 7).
Figure 7. Access to the archived lectures
The evaluation by students, staff members, and faculty is currently being carried out through the online survey system[3] on the SOI site.[4] A more thorough evaluation will be put together by mid-February.
The success of this course proves that next-generation Internet technologies are already being used well in education. This experimental course has shown that next-generation technology can help students get the best lectures on specific topics from all over the world and university professors can construct their courses using those lectures, thus giving students a great learning opportunity.
This project is supported by the WIDE project, WISC, KEIO, and NAIST. Special thanks to Sam Etler and Bill Jensen at WISC; Kengo Nagahasi and Akimichi Ogawa at KEIO; and Masafumi Oe and Naoto Morishima at NAIST for the quality of technical support for this project. Thanks to Yuri Akita, Takeru Nomura, Yoko Murakami, Koji Ogawa, Koshiro Mitsuya, and Syoichi Yokoyama for helping with lecture operation. Special thanks to Kazunori Sugiura, Hideki Sunahara, Osamu Nakamura, and Hiroshi Esaki of the WIDE project. The WISC Computer Science Lab helped us in many ways to make this happen. Finally, special thanks to APAN and JGN for very high speed network support.