Jo Feb 12, 2024

Ryu Chang Sik, a section head at the Faculty of Distance Education, has developed a large-scale online lecture system in relay mode.

The relay system is an information system capable of providing thousands to tens of thousands of simultaneous subscribers with real-time online education on a nationwide scale in three-tier relay mode through central server, intermediate server, terminal server and terminal on a computer network.

The system aimed to narrow the difference in the level of education between the capital and other provinces and between cities and countries by providing real time or non-real time lectures given by competent lecturers from the capital and other cities to all the schools across the country. Therefore, it has to be designed to transfer real-time lecture data from the capital to provinces, from provinces to counties and from counties to schools, not from the central or provincial server to all terminals.

First, he newly designed and realized a three-stage relaying system via centre-province-county-terminals. Then he solved some technical problems like increasing compression ratio and reducing network load to deal with increase in network traffic per subscriber of three to five times more than the existing video conferencing system, and enhancing the real-time transmission of video and audio data in the relaying mode for perfect performance of online lectures.

Second, he applied load balancing to avoid network overload at provincial, city and county network stations.

Next, as relay servers are installed in all provinces and hundreds of counties across the country, he correspondingly solved the problem of transferring and synchronizing history data between central, provincial and county servers so that a detailed report on attendance in the provinces, cities and counties can be made to the center.

Finally, he made it possible to hold multiple conferences including academic uniformity as well as online lectures.

The proposed system will make a positive contribution to narrowing the differences in education levels between the capital and other provinces by stepping up IT-based education.