ReLaTe

1. ReLaTe Remote Language Teaching using videoconferencing DIDASCALIA

2. Background • Collaboration between Exeter and University College, London • Exeter: Project Pallas (Humanities Computing) • UCL: Dept of Computer Science • Early example of Internet videoconferencing • Started 1994 • ReLaTe: specifically for language teaching • BUT also used for wide range of educational applications DIDASCALIA

3. Videoconferencing over UK SuperJANET network • SuperJANET links all UK universities • High speed backbone • 155 or 34 Mb • 10Mb SMDS to other sites DIDASCALIA

4. ReLaTe trials • Tutors and students - at any UK university • initially just Exeter and UCL • subsequently others, including Aberysytwyth DIDASCALIA

5. Internet videoconferencing:background • Early development - CU-SeeMe • available from Cornell University • commercial version now from WhitePine • NetMeeting • freeware from Microsoft • Initial versions limited to one-to-one • Now allow multi-way via MCU/reflector technology DIDASCALIA

6. ReLaTe: MBone videoconferencing • MBone (Multicast Backbone) • Like other Internet video-conferencing - uses IP protocols • Is an overlay network that enables multimedia to be sent efficiently over the Internet • Particularly important for multiway videoconferences • Mbone tools - freely available DIDASCALIA

7. Hardware requirements • System runs on: • PCs (Windows 95 or Linux) • Unix workstations • Small hardware requirements: • Sound card… • but full duplex problems • Camera and video capture board • Hauppage camera and Win/TV board on PCs DIDASCALIA

8. ReLaTe session DIDASCALIA

9. Individual MBone videoconferencing tools • Video - vic • developed at Lawrence Berkeley Labs, California • Audio - rat • developed at UCL • repairs packet loss through redundancy • Shared Workspace - wb • developed at LBL • not available for Windows 95 (no source) • Shared Text Editor - nte • developed at UCL DIDASCALIA

10. Screenshot of ReLaTe session DIDASCALIA

11. ReLaTe interface • Much easier for novice users to control than multiple windows • Has maximum of 4 or 8 users • if four, can click on one to give bigger window • powermeter beside each window for visual indication of who is speaking • Audio controls • overall volume for input and output • Shared workspace • Switch between whiteboard and text editor • colour shows who is adding annotations DIDASCALIA

12. Advantages of MBone desktop videoconferencing • No studio needed, use in own office • Uses existing network infrastructure • Platform-independent • Uses readily-available hardware • Software: free, in public domain • Conserves network bandwidth • Multiple video streams DIDASCALIA

13. Disadvantages • No reserved network bandwidth - quality very variable • Video - not high quality • frame rates often only 4/5 frames/second • Software coding/encoding means high-load on CPU • Lots of network and system configuration required • need for MBone routers to be installed • hard to control on large bridged or switched networks DIDASCALIA

14. Comparison with other forms of videoconferencing • Compared with ISDN • ISDN guaranteed quality, but recurrent line costs, and multiple video streams not easy to achieve • Compared with broadband ATM • ATM gives MUCHbetter quality and guaranteed quality, but much greater bandwidth demands • MBone - relatively small bandwidth demands • MBone - relatively low bandwidths • 80-100K for each video channel • 60K - each audio channel • eg 4 participant conference takes 0.6 Mb/sec DIDASCALIA

15. Coping with variable quality • Audio quality much more critical than video • users can cope with video being jerky or stopping • Video - still useful even at low frame rates • gives way of judging reactions, body language etc • Audio tool - redundancy • sends second copy of each audio packet • if first packet lost or delayed, copy played out instead • enables sessions to continue even when considerable packet loss DIDASCALIA

16. Language teaching trials • ReLaTe system - now used for many trials • mostly specialist short courses, eg French for Lawyers, Mandarin • some longer, accredited courses eg students in second year of Intermediate French • results promising, but small numbers (4 students • taught in two groups of 2) make direct comparisons difficult DIDASCALIA

17. Feedback from language teaching trials (1) • MBone videoconferencing - good for small group tutorials • where genuine two-way interaction • Seems less good for lectures • send copies of videotapes to remote sites instead? • Variable quality of audio and video • problematic, but tutors and students coped OK • lip synchronisation desirable, but not essential for most types of language work; needs high video rates to work satisfactorily DIDASCALIA

18. Feedback from teaching trials (2) • Importance of shared workspace • whiteboard no longer solely belongs to tutor • students prize ability to add comments • perceived as very important for language work • Integrated interface - well received • Importance of full-duplex audio • tutorial teaching doesn’t flow if have to ‘click to talk’ • Effect on tutorial styles • tutors seem to need more directed style, eg asking specific students, rather than throwing question open DIDASCALIA

19. Feedback from teaching trials (3) • Group dynamics - very interesting • seeing your own image on screen - eg looking bored! • students feel they know remote tutor, even when never met them face-to-face • tutorials - seem more concentrated • Physical constraints • eg headsets tiring after some time DIDASCALIA

20. Integration with other technologies • Use of Web material • tried discussing material on Web, but synchronisation problems if each user has own Web browser • read individual Web pages into whiteboard, which worked very well • Use of video clips • play out video clip into conference, instead of one participant • need better quality, because more movement than ‘head and shoulders’ view of live participants DIDASCALIA

21. Future teaching developments….? • Need for students to be able to work on own • eg like language laboratory mode, where tutor listens in • NetMeeting, gives ability for tutor to see student running application (eg CALL package) on local computer • alternative - use of multi-way Web browsers • Need for tutorial to split into sub-groups • tutors want ability for small groups of students to be able to work without tutor - and then come back to original group and discuss results DIDASCALIA

22. European potential • Gives possibility of access to foreign tutors - and direct access to foreign students • MBone - international network • technically feasible, but in past, bandwidths too low • TEN-34 network • EU-funded infrastructure • links European research networks DIDASCALIA

23. DIDASCALIA

24. European trials • ReLaTe - carried out initial trials with Germany • University of Wuerzburg • problematic, but sufficiently successful to try further work… • problem of low multicast limits imposed by networks, even when high total bandwidths • DANTE - soon moving to 155MB • for details, see: http://www.dante.org.uk DIDASCALIA

25. Future technical scenarios • New versions of IP protocol - gives guaranteed Quality of Service • Greater use of H.323 tools • eg NetMeeting, CU-SeeMe • once they support multi-way conferences adequately • Other challenges • handling large multi-user tutorial/seminar style videoconferences • eg many thumbnail windows, plus voice activated larger window? DIDASCALIA

26. Some Web addresses • Videoconferencing tools used in ReLaTe - SHRIMP project • http://www-shrimp.cs.ucl.ac.uk/shrimp/ • NetMeeting • http://www.eu.microsoft.com/netmeeting • WhitePine CU-SeeMe • http://www.wpine.com/products/CU-SeeMe • WhitePine MeetingPoint • MeetingPoint is Multipoint Controller software • http://www.wpine.com/products/MeetingPoint DIDASCALIA

27. And (at last) THE END • ReLaTe • http://www.ex.ac.uk/pallas/relate/ • John Buckett - University of Exeter • J.Buckett@exeter.ac.uk DIDASCALIA