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Development of Multipoint Communication Systems for Remote Seminar. Toshihiro Hayashi and Yukuo Hayashida Department of Information Science, Saga University E-mail: {hayashi, hayasida}@is.saga-u.ac.jp. Background. Remote education is getting popular.
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Development of Multipoint Communication Systems for Remote Seminar Toshihiro Hayashi andYukuo Hayashida Department of Information Science, Saga University E-mail: {hayashi, hayasida}@is.saga-u.ac.jp
Background • Remote education is getting popular. • Large scale of remote education: for lecture • Small scale of remote education: for seminar • Seminar is generally synchronous activity. • Same time and same location • Seminar always needs arranging time and location among the learning group • Sometimes, some members cannot attend the seminar by restrictions of time and location (absentee problem). • Utilization of computers for solving the restrictions of seminar • This changes synchronous seminar into asynchronous seminar
Asynchronous seminar • Solutions for time restriction • Asynchronous communication tools: e-mail, electronic bulletin board system and so on. • Assistance tools for absentee: video archives and so on • Solutions for location restriction • Synchronous communication tools: electronic conference system (NetMeeting, CU-SeeMe, and so on) • These systems change seminar into remote seminar
Our research questions • Development of a computer supported remote seminar environment • Model: What is remote seminar model ? • Architecture: What kind of system architecture is appropriate for remote seminar ? • Implementation: How to develop communication systems for realizing remote seminar ? What kind of techniques are needed for the implementation ? • Evaluation: Do our systems work effectively in the situations of remote seminar ?
Seminar model CA Professor Students Same time but different locations Remote seminar 1 Professor Students CA Same time and same location Normal seminar CA CA: Computer assistance Professor Students Same time but different locations Remote seminar 2
Features for remote seminar in our research • Remote seminar consists of max five members. • Each member has one PC for seminar. • All PCs are connected to information network (Internet and so on) to transmit data. • The members are generally in different rooms/locations. • Some members might be in the same room/location. Information network
Communication systems for realizing remote seminar • System requirements • Multi-point communication • For data transmission for small group via information networks • Flexible system configuration • For various kind of situations of “Same time but different locations”
Server Multi-point communication (1) Server based multi-point communication Peer to peer multi-point communication
Multi-point communication (2) • Server based multi-point communication • Typical style of existing electronic conference systems • Some existing server based systems are high-cost (for example, MeetingPoint: $8,995 for 10 user license) • At least, one sever machine must be prepared. • There are free servers but we cannot always use them. • Peer to peer multi-point communication • This type of communication needs no server. • This type of communication generally requires high-performance PC for each user
Existing network applications available for remote seminar • Classification of network applications • Single-function applications • have one or a few operations for single medium data • Example: CD player (Windows accessory) • Multi-functions applications • have plural functions for various kind of media data (multimedia data) and handle them together • Examples: NetMeeting and CU-SeeMe
Remote seminar system Remote seminar system App1 Media1 Media1 App1 App2 Media2 Media2 Core application App4 App3 Media3 Media3 App5 App Multi-functions application App Single-function application System construction models Multi-Functions on Single Application model MFSA model Multi-Applications with Single Function model MASF model
Features of system construction models • MFSA model • Remote seminar system is constructed by only one multi-functions application • Core application centered system --- low flexibility • Actual examples: NetMeeting, CU-SeeMe • MASF model • Remote seminar system is constructed by plural single-function applications • Integrated and complementary system --- high flexibility • Actual examples: MBone applications (VIC, VAT, WB, and so on)
Overview of our system development • MASF based communication systems • VCRS (Video Communication tool for remote seminar): video data transmission system • RCS (Remote Chat System): sound and voice data transmission system • RPS: remote presentation system • RWB: remote white board • Prototype implementation on Linux • Linux is free OS and provides free system development environment.
(2) RPS: Remote Presentation System (1) VCRS: Video Communication tool for Remote Seminar (2)RWB: Remote White Board Interface of remote seminar system
Consideration (1) • Problems of system use • It is complicated for users to combine our communication systems for remote seminar. • Necessity of a support system for integrating our communication systems. • It is bothersome for users to connect all hosts for every communication system. • Necessity of an auto control system for host connection.
Speaker Mike User Camera User requests ACU: Auto Configuration Unit Monitor KB & mouse User Interface Control Database GUI Control VCRS RWB Communication System Control Module Configuration pattern RPS RCS Transmission Control Recorded seminar data Presentation documents MHB: Media Handling Block To other hosts Information network Communication systems From other hosts Configuration of remote seminar system ACU: support system for integrating communication systems MHB: auto control system for host connection
Consideration (2) • Problems of operating system • There are hardware restrictions, for example video chip, to use our communication systems on Linux. • Linux is not so major compared with Windows. Porting of communication systems into Windows
Summary • Development of remote seminar system • Prototype implementation of communication systems on Linux (kernel: 2.4.5, distribution: Turbo Linux workstation 7.0) and Windows (Windows 98SE, 2000 and XP) • Future work • Implementation of ACU and MHB • Field test of remote seminar system using Internet and JGN (Japan Gigabit Network)