New Tools In Education

1. New Tools In Education Minjun Wang Department of Electrical Engineering and Computer Science Syracuse University, U.S.A mwang03@syr.edu

2. Outline • The Big Picture • Collaboration Architecture • The Master Client Application • The Participating Client Application • The Event Models • Narada Message Broker • Instant Messaging Web Services • Metadata and On-demand Education

3. The Big Picture • Collaborative PowerPoint applications for distance education, e-learning, and online conferencing • One of which is a Master client, the others are participants • The presentation files are deployed or downloaded beforehand to the hosts of both master and participants clients, and in the same directories. The MS PowerPoint is installed on all the hosts. • Use small text-based event messages to communicate between the master and participants, compared to image data communication as in Shared Display; thus lower network traffic and improve performance. • The Master client captures events and sends the event messages to participants during its presentation; the participants then render and share the presentation screens synchronously with the master. • Narada Message Broker as the underlying message communication system • It transmits event messages between the collaborative PowerPoint applications’ master and participant clients • Web Services as building blocks of collaborative applications • Instant Messenger Web Services • Event metadata as Web Services and on-demand education

4. NaradaBrokering Message Service Event Messages Event Messages User 1 User 2 User n Master Client IUnknown Outgoing interface Connectable Object Sink Connection Point Collaboration Architecture

5. The Master Client Application (1) The master client is the one that captures events during a PowerPoint presentation and sends messages to participating clients for rendering. Technologies used: • Automation enables applications to expose functionality through interfaces, which can be reused by other applications through wrapper classes. • Connectable objects manage Connection Point objects where events are defined, and therefore are the event source.

6. The Master Client Application (2) • The sink interface is where the handlers of events are implemented; the Master client handles events fired from the connectable object through the sink.

7. The Participating Client Application (1) The participating client is the one that receives messages from Narada message broker, and renders the presentation display. Technologies used: • JNI (Java Native Interface) Cooperation between Java and C/C++ • Wrapper Classes, Dispatching and Automation.

8. The Participating Client Application (2) The cooperation between the message broker and the participating client, and the mechanism of it.

9. The Event Models (1) Three levels of events: • Physical events mouse over, mouse clicking, keyboard stroking, etc. • Semantic events meaningful instructions such as change slides, change windows, etc. • Rendering events Rendering of presentation displays via automation, according to the semantic event messages received.

10. The Event Models (2) Events that are posted in “EApplication” interface of PowerPoint and that can be captured and processed.

11. Narada Message Broker (1) It transmits event messages between the collaborative PowerPoint applications’ master and participating clients It can be deployed as a Grid in Peer-to-Peer Grids, using robust, secure, structured and powerful machines and resources. • It supports messaging in Peer-to-Peer Grids • It uses a generalized publish-subscribe mechanism • It handles dynamic protocol choice, tunneling through firewalls • It supports TCP, UDP, multicast, SSL and RTP • It is error tolerate, supports dynamic routing, secure message, and full scalability.

12. Narada Message Broker (2) • It can run in client-server mode like JMS (Java Message Service) or in distributed Peer-to-Peer mode like JXTA • It can be used in real-time synchronous collaborations

13. Instant Messaging Web Services (1) Web Services are building blocks in Peer-to-Peer Grids computing. Web Services enable developers to integrate functionality across businesses and organizations. • The structure of Web Service • Publish, Find, and Bind • URI (Universal Resource Identifier), WSDL (Web Service Description Language) and UDDI (Universal Discovery, Deployment and Integration) • The elements of Instant Message • XML (eXtensible Markup Language) tags • DOM (Document Object Model) format • SOAP (Simple Object Access Protocol) protocol

14. Instant Messaging Web Services (2) The structure of Web Service in general, and the Instant Messaging Web Service with the applications in particular

15. Metadata and On-demand Education • Description tags and properties attach the event messages by using the functions in Instant Messaging Web Services; these metadata are saved and accessed by functions of Metadata Web Services. • A special version of the collaborative applications inherits the functions of both the master and participant, and makes use of the Metadata web services to access the metadata. • Users subscribe to a topic via session servers, and use the special version to access the metadata to render and review the sessions once happened at their own pace. This is used in On-demand education.

16. Conclusions • The Collaborative PowerPoint applications integrate the master and participating client processes; cooperate with the NaradaBrokering message service; leverage the Instant Messaging and Event Metadata web services, and can be used in On-demand education. • It can be used in distance learning, lecturing, conferencing, etc. • It has the strength of small text event message communication, and thus high performance and efficiency. Its limitations include it’s hard to use in hand-held devices like PDAs.

17. Future Work • Dynamic generating and deploying Metadata Web Services with a session server. • Integrating the Collaborative PowerPoint applications with Audio/Video system to bring multimedia into virtual classrooms. • Improving the animation and sounds parts of the applications.