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Ayman Abdel-HamidDepartment of Computer Science
Lamar UniversityP.O. Box 10056, Beaumont, TX 77710, USA
Kurt Maly, C.M. Overstreet, Sahar Ghanem, Ye Wang, and Aravind Elango
Department of Computer ScienceOld Dominion UniversityNorfolk, VA 23529, USA
{maly, cmo, ghanem, ywang, aelango}@cs.odu.edu
Tool Sharing Modes in aSynchronous Interactive Remote
Instruction System
June 2004 ED-MEDIA 2004 2
Outline
Introduction IRI-Easy Overview Tool Sharing Modes in IRI-Easy
Application Server Mode Remote control capability
Local Sharing Mode Conclusions and Future Work
June 2004 ED-MEDIA 2004 3
Introduction 1/2
IRI-h (heterogeneous) is a multi-platform, multi-network environment scalable system (available from http://www.cs.odu.edu/~iri-h)
IRI-h prototype successfully used to teach a semester-long computer science course across 2 sites 20 miles apart
IRI-h prototype deployed in actual home user scenario using a cable modem connection
IRI-Easy, most recent version of IRI
June 2004 ED-MEDIA 2004 4
IRI-Easy features: fully implemented in JAVA (multi-platform) Simple on the fly setup of collaborative sessions audio, and video (Java Media Framework JMF) tool sharing (Interactive Program Video IPV) annotation and pointer Application-level gateway
“Group of groups” communication paradigm Individual multicast-disabled participants
recording and playback note taking and notes-server call student, site video
Introduction 2/2
June 2004 ED-MEDIA 2004 5
IRI-Easy Overview 1/4
SMSP1
SP3
SP2
Multicast Intranet I
Site2
GW1 GW2
SP5
SP4
Multicast Intranet II
Unicast UDP forwarding
TCP connection(control and state)
DirectoryServer
Multicast-disabled participantMulticast-disabled participant
June 2004 ED-MEDIA 2004 6
The concept of a session shared view and private view Secure session vs. open session
a directory server offers a lookup service for ongoing sessions Contacted by an IRI-Easy client software to get active
sessions’ information unreliable group communication offered through IP-
multicast semi-reliable group communication offered through IP-
multicast and a controlled retransmission policy IRI-h services: audio, video, tool-sharing, annotations, and
pointer services.
IRI-Easy Overview 2/4
June 2004 ED-MEDIA 2004 7
IRI-Easy Overview 3/4
A snapshot of the IRI-Easy client software while viewing active sessions’ information
June 2004 ED-MEDIA 2004 8
IRI-Easy Overview 4/4
A shared view snapshot illustrating a discussion scenario
June 2004 ED-MEDIA 2004 9
Tool Sharing Capabilities Identified tool sharing as one of the essential features of
interactive distance learning systems A tool sharing engine: allows a participant to share any
running application with other participants sender side (coded in Java, relying on some native calls in
Microsoft Windows) images of the windows in the application being shared are
captured, compared to previous images to detect change, compressed, and transmitted over a group communication channel
receiver side (pure Java code, using Java Advanced Imaging package) images are received, decompressed, and displayed
a floor control facility is provided to enable receiver side participants to take control of the shared tool
June 2004 ED-MEDIA 2004 10
Tool Sharing modes: Application Server mode 1/3
Server machine to act as sender side: Application server Hosts a variety of applications needed for class material
presentation and discussions does not participate in shared session activities such as
video, audio, and shared tools traffic reception requires a system administrator to man the application
server capable of retrieving a list of currently active applications
on the machines (through the sharing tool engine) Out-of-session communication mechanism between current
presenter and administrator to dictate which tools to be shared next
chosen application window(s) needs to be on top of other existing applications
June 2004 ED-MEDIA 2004 11
Tool Sharing modes: Application Server mode 2/3
Need for remote control of application server Application server configured with names and locations of
applications available for sharing Application server registers with SM Participants provided with capability of remote controlling
the applications server, including starting new applications initiating the sharing process for an already running
application changing the size and the location of the shared application
window All protocol communications are sent to the SM, which in turn
relays them to the application server, and vice versa in the reverse direction
June 2004 ED-MEDIA 2004 12
Tool Sharing modes: Application Server mode 3/3
An image of the shared application window
A miniature of the application server main screen along with shared application window
Remote control interface
A remote control scenario of the sharing tool engine on the application server
June 2004 ED-MEDIA 2004 13
Tool Sharing modes: Local Sharing mode 1/2
Relying on the application server as single source of applications to be shared represents a single point of failure.
Need for local sharing mode (peer to peer)Any participant can share any running tool on his/her desktop
Intelligent manipulation of IRI-Easy GUIa participant has to control the GUI and the shared tool, with the requirement that the shared tool remains on top at all times for correct capture process operation
Solution: Automated GUI resizing policyvisible screen is split in half with one half being occupied by the IRI GUI, and the other half left available to place the shared tool in
June 2004 ED-MEDIA 2004 14
Tool Sharing modes: Local Sharing mode 2/2
Shared tool
IRI GUI automatically resized to provide space for the shared tool
An image of the shared window as part of IRI-Easy GUI
a local tool sharing scenario
June 2004 ED-MEDIA 2004 15
Conclusions
IRI-Easy On the fly set up and join of collaborative sessions Caters for heterogeneous network environments
Sharing tool engine (IPV) Two tool sharing flavors
Application server mode Local sharing mode
Versatile sharing scenarios enhancing teaching and learning experience in interactive distance learning systems
June 2004 ED-MEDIA 2004 16
Future Work
investigate the feasibility of simultaneously combining both tool sharing modes within a session
automate the discovery of applications available on the application server removing the necessity for pre-configuration of application server
port the sharing tool engine sender component native calls into other platforms such as Linux