We visited Ms. Kaori Madea at Hiroshima City University who conduct various remote collaboration and interviewed its technological and operational issues.

It is distance collaboration in the field of education and I conducted an experiment using JGN in a real-world class room situation such as elementary school, junior high school and high school. As I mention later, giving seminars at our university via JGN is conducted on daily basis.

Firstly,activities that are limited within our university will change to activities will be reciprocal among schools, distance interchange is significant.

Secondly, there was an effect of technological transfer from the university. For the experiment a system in the making is being used. To be honest with you, this system is not a sophisticated software such as packaged products, some of the professional users expressed reaction that is close to advised reaction. However, when we think of technological transfer from the university, it will be a good example for outsiders to use the system in a practical manner. Nowadays, technological transfer form the university is emphasized as a great importance. In a social meaning, this is a good experience as a trial of technology transfer. For our university we can get good feedback. For those who do not have technical knowledge, it is required to explain its usage and unexpected device will be necessary and for the students who created program, although they feel that they have completed their program, due to the result of an unexpected operation, there must be many faults. Further, school teachers who are users also comment that it was an stimulant experience to get in touch something new.

Does it mean that the usage of broadband was researched at the elemental schools, junior high schools and high schools?

This is hen-versus-egg question and in order to cut the vicious cycle of the usage of broadband, the best way is to use it.

For younger students, the demand for the quality is unrelenting. University students accept the situation even there are some drop on the images but for the elementary students claim that "Something is wrong."

When we see Web page only the communication quality does not bother us that much but in the case of the application that requires bands of images and voice transmission, demand for the quality becomes higher. Even the transmission of the images and voice, depending what kind of the information you are to send, demand for the qualities vary. In a one-sided lecture type doesn't bother the viewers even there are some skips of the images but instruction of dance for example, if some of the images skips, the viewers cannot follow the movement so the demand for the quality increases. Same can be said for the audio delay. the viewers are not bothered if it is one-sided but if it requires interactive communication, delay of the discussion will be a problem.

Further, we challenged to realize a distance chorus this time. The chorus which has soprano and alto parts make us feel uncomfortable with a slight delay of time. This distance chorus was was archived by expanding RAT open source audio transmission system. This year too, we plan to utilize JGN either around the December of 2002 or January of 2003. For your information, when we think acoustic velocity, it takes 0.07 seconds to transmit 24m and this level of delay is the scope for permission since you can see this delay in actual orchestra.

At the Special Session of JGN Symposium held in Nago city in Okinama the year 2001, Okinawa's performing art of falk Eisa scenes of dancing eisa was transmitted from Hakushima elementary school in Hirosihima real time. I wanted this eisa dancing which was practiced at the athletic festival to those elementary school children in Okinawa. This eisa dancing attracted rinkenband's attention to the troupe that was after all and they were asked for performance. So in February of 2003, Linkenband and Hakushima elementary school are planning to have distance collaboration.

Moreover, this is not the experiment using JGN directly we had an International Exchange event between Thailand and Hiroshima. Since the Asian Games which was held 1994 in Hiroshima, network exchange have been continued between elementary schools. It was an even connecting in band of 500kbps and introducing cooking by Thai rice and sweets made from Japanese rice. This event was very impressive since a mother whose child is in Japan questioned her child in Japan saying 'Aren't you cold there'? and some children started to cry being filled with emotion. At Thailand side the whole operation was asked to AIT, which is a university of Thailand and since this was the first time for them, they appear to have a mild embarrassment at the beginning but in the end they had sense of accomplishment.

One of the largest-scale event using JGN is Live Eclipse in 2001. At the gym of an elementary school, we all saw African total eclipse of the sun that is the opposite of the earth via live hookup and at the moment of the eclipse, the crowd gave a deafening roar.

Pease tell us the technological point in research.

Regarding transmission of the images and audio, increasing robustness and decreasing delay trade-off relationships. We implemented interface that can change three mode setup such as chorus mode (small delay, small robustness) conversation mode (middle delay, small robustness) and transmission mode( large delay, large robustness). To put a practical manner, we think it is necessary to have this mode and our implementation is the very first trail.

For image transmission we use MPEG2 transmission system (MPEG2TS) which has been developed centering Hiroshima University. This is MPEG2 images transmission that has error recovery function and if its ross rate is certain even it generate packet on the network, it will automatically recover from its error and realize the transmission of the high quality images. This development is also being promoted as a advertising project of JGN, Most cases of the exchanges undertaken as projects use MPG2TS is used and it can realize image transmission of TV quality with the network that has only 10 Mb ps so an active exchange is possible. Since our project use this system quite often it is useful for debugging.

Please tell us some of the painstaking points in its operation.

Having conducted several school exchange projects, I really feel the importance and necessity of coordination between people and people. Currently researchers at the university are doing this role but sometimes I wonder the existence of a professional coordinator. It might be better to have a support system including prefectual boards of education and among system relates school education.

Please tell other important topics regarding research.

Recently broadband environment has penetrated. Even at home the diffusion rate of ADSL is remarkable. It is not rare to lay down 100Mbps class line at the backbone of the companies or universities but obtaining 10Mbps band line at end end is quite tough. It is because it still remains the half square setup or cases such as switches and hubs are problematic. This pain on the network cannot understood immediately thorough the usage just looking a web only. When animation and audio are transmitted you will instantly notice that there is a problem on the network. Yet you won't know where in network is wrong immediately.

So network diagnosis and measurement technology will be more and more important. Even at the present, a case of an event it will be a problem without fail. when animation and audio transmission penetrate further, diagnosis and measurement technology will penetrate as well. Lately Gigabit class divide in on the market but technology to identify the performance described in the specification is not matured yet.

I heard that you are conducting distance seminar.

Via JGN, we conduct distance seminars every week for one and half hours at Hiroshima University, Hiroshima City University, Saga University, and Wakayama University. Currently it is a circle style seminar whose theme is IP v6. We use MPG2TS for interactive communications and since its delay is problematic, regarding audio transmission we use system which is under development( MRAT). Synchro of the audio and images are not taken yet but regarding the sound its delay is being minimized quite a bit. Due to the event devices are moved often and it takes time to setup but this point has educational effect as well. In practice, for students and teachers it is stimulative and very interesting matter. Tokyo and Osaka has large number of researchers but a local city like Hiroshima has paucity of the researchers so it is grateful to have opportunity to promote research and study together via network. I realize that since attention to give better lecture than other university affects and educational effect is more than expected.

Pease comment us some of the painstaking point on it usage.

By coincidence, when the World Cup was held there was a lot of packet loss from Saga University. So this trouble Ethernet part rather than ATM parts. Especial when the alternation switch for total square and half scare is a cause of trouble. Supposing that the switch is automatic so when we expect automatic alternation for full square, its setup remains to be half square. Especially in the case of this project, since network in Hiroshima prefecture has only 10 Mbps band, communication is not enough and we suffered from trouble shooting. We also use IPv6 that is not largely different form IPv4. Yet in case of multicasts, there some routers that can not correspond to it. Regarding multicasts if device as IPv6 specifications penetrate, there is no need to setup manually there is a possibility of penetrating multicasts itself. When we talk about multicasts its image is effective use of backbone but multicasts in LAN might penetrate surprisingly. On campus, an use to give lecture by delivering multicasts can be considered.

What do you evaluate JGN after using it?

For us what was good about JGN is when a human network was established, something could continuously done. We have used JGN for various events and to penetrate a new technology it is indispensable to have phase such as experience it. Those events that we held had a large number of participation so although was an experiment we had high feeling of attention. Another important point was that JGN is stable. We are heavy user of the JGN since our daily research will be disrupted without JGN so we are hope its continuous use for some form definitely.

Value of this kind of testbed lead to have abundant access points. In the future it would be better to connect to overseas such as internet 2.

It was persuasive comment intermittent practice I would like to extend my gratitude for Ms Maeda who interviewed for us out of her busy schedule.

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Hiroshima City University
School International Exchange over the Internet between Minami-Kanon Elementary School in Hiroshima and Prachaniwet School in Thailand
RAT(Robust Audio Tool)