ACM SIGUCCS 2009, 10/12 @ St. Louis

1. A Casual Teaching Tool for
Large Size Computer
Laboratories and Small Size
Seminar Classes
Takashi Yamanoue
Kagoshima University

2. Contents
1. INTRODUCTION
2. OUTLINE OF SOLAR-CATS
3. MAKING A GROUP OF NODES
4. USING FUNCTIONS
5. EXPERIENCES
6. RELATED SYSTEMS
7. CONCLUDING REMARKS

3. 1. INTRODUCTION
 Teaching tools (for Computer Lab.)
 Teacher’s Screen -> Students’ Screens
 popular and effective.
 Need Servers
 require
 significant time and energy by the manager
 Not only computer Lab.
 ad-hoc seminar classes
 hard for most teachers to maintain their own server.

4.  SOLAR-CATS
 A teaching tool
 for large size computer laboratories and small
seminar classes
 To meet this need.
 does not need a server … P2P technology.

5.  Functions.
 Remote operation
 Interactive operation … mutual exclusion
 The sending of images
 The recording and replaying

6.  Using SOLAR-CATS for
 Introductory computer literacy classes
…5 yeas, about 50 students/class
 Network security class…2years, 30 students
 Seminar classes … 3 to 8 students
 Actual size letters and pictures
 Some students requested it
 No support from the lab manager
 USB keys to students.

7. 2. OUTLINE OF SOLAR-CATS
 A WYSIWIS (What You See Is What I See)
 Enables sharing real-time operation of
 Applications
 text editor
 draw
 a simple programming environment
 web browser
 writer’s assistant , …
 All equipped with SOLAR-CATS.

8.  Consists of
 node systems (nodes)
 a group manager.
 Each node system
 Applications
 A main controller
 A command transceiver
 An event recorder/player

9. Group Manager
Teacher’s node system
TCP TCP Student’s node
Student’s node system
system
TCP
TCP TCP TCP
Student’s node Student’s node Student’s node Student’s node
system system
system system

10. Writer’s Assistant
Web Browser
Programming Environment
Text Editor
Draw
Applications
Main Controller Command Event Recorder/
Transceiver Player
Network

11. 3. MAKING A GROUP OF
NODES
 The video of making a group of nodes

13. 4. USING FUNCTIONS
 Remote Control of an Application
 Interactive Operation of an Application
 Still Image Broadcasting
 Recording and Replaying

14. 4. USING FUNCTIONS
Remote Control of an
Application

15. 4. USING FUNCTIONS
Interactive Operation of an
Application

17. 4. USING FUNCTIONS
Still Image Broadcasting

21. 4. USING FUNCTIONS
Recording and Replaying

23. 5. EXPERIENCES

31. 6. RELATED SYSTEMS
 Commercial systems (like DyKnow)
 Server
 The electronic chalk board
 Uni-direction
 QuickBoard… web based WYSIWIS
 It uses a high performance server
 Uni-directional.

32.  Multi VNC … is an extended VNC
 No mutual exclusion.
 Wb … interactive draw
 No mutual exclusion.
 ESM, RelayCast and Emma
… ALM (Application Level Multicast)
 exchanging streaming data
 No sharing the same operation.

33. 7. CONCLUDING REMARKS
 SOLAR-CATS
 A real-time and interactive instruction tool
 For large size computer laboratories and small
size seminar classes
 P2P
 transmitan operation at one PC to other PCs in short
time without any errors
 A mutual exclusion algorithm
 realize a bidirectional sharing of the operation.

34.  Problems
 The group would form incorrectly
 when many nodes attempt to join a group in a short
time
 The new node does not get access to the
common data immediately
 When a new node joins the group, if other nodes are
sharing common data
 Fixing now.

35. ACKNOWLEDGEMENTS
 Grant-in-Aid for Scientific Research of Japan
Society for the Promotion of Science,
Fundamental Research(C), 17500041

36. You can use it Now!
 http://yama-linux.cc.kagoshima-u.ac.jp/
~dsr/solar-cats.html
 http://10.250.3.10/w/ … This PC
 Sorry. It seems, it does not work now.
 At Your Own Risk!
 This program has a remote control function.
 You can re-distribute the program for
educational use.
 I can help you to install it and to run it now.