1. Performance and Scalability Issues of Multimedia Digital Library
Lakshmi, Manjunath, Vamshi,
Raj Reddy
19th Nov 2006
Good Morning, This is Manjunath. I wrote a paper along with Lakshmi Pratha and Vamshi Ambati. Our paper discusses about Performance and Scalability issues in Multi Media Digital Library.

2. Architecture of Multimedia Digital Library@2006
Objective
To address the growing need of Multimedia information sharing across the internet by providing high performance and a highly scalable architectural framework for Multimedia Digital Library.
4/21/2019
Architecture of Multimedia Digital

3. Multi Media Digital Library
Libraries being able to host all varieties of media like audio, video and text content.
Providing staff / customers to upload content to the servers (offline application or web app)
Interface to search and locate required content
View the content without interruptions / delays.
What is an Multi Media Digital Library? The ones which will be able host all kinds of data (video, audio, text etc.).
What can a Multi Media Digital Library do? It should provide the catalog and search features for its customers. It should provide the available information with out any delays and interruptions. It should provide an interface to update the available content. And many more applications that might come in future.
4/21/2019
Architecture of Multimedia Digital

4. Existing Systems and their Limitations
Informedia II
A Video Visualization and Summarization Tool
Does not address the performance or scalability requirements
MDLTR
A Tool that handles the multimedia data management
Addresses only the database structure to be implemented for the Multimedia Digital Library
ASIS MDL
Uses separate servers for each format of the multimedia in order to facilitate the streaming and play the files at the client system.
Indexing and Searching using keywords.
Some of the existing works done on Media Digital Libraries like Informedia (a video visual, summarization tool), MDLTR, ASIS MDL (is a web based digital library application, using different servers for different formats) help us in searching and indexing video content, video summarization and visualization, database structures for multimedia digital libraries. None of them provide the framework required for similar applications.
4/21/2019
Architecture of Multimedia Digital

5. Architecture of Multimedia Digital Library@2006
What are we trying to do?
Addressing performance, scalability issues involved in media digital library at Architectural level.
Provide Architectural Framework to similar applications.
What we are trying to do in our paper is address the performance and scalability issues at architectural level. We are trying to provide a generalized framework for similar applications. So, How would you increase the performance of an application? How would you measure performance? By increasing through put and reducing the response time.
4/21/2019
Architecture of Multimedia Digital

6. Architecture of Multimedia Digital Library@2006
Throughput
Large file size of the content
Delay in client access
Increased throughput with Stripping
Throughput can be termed as amount of work an application can perform in one unit of time (like messages per second, frames per second, transactions per section). Due to relatively large size in data, we have delay in access at server end. To avoid such delays we propose striping of the media file. Which means each media file submitted to the system will be cut into segments and stored in multiple logical/physical drives. That way throughput at server end will be more.
4/21/2019
Architecture of Multimedia Digital

7. Architecture of Multimedia Digital Library@2006
Response Time
Congestion
Media file access time at server
Response time could be amount of time taken to access required content/amount of time server takes to deliver. If a user wants to access particular minute of an hour lecture, traditionally buffering time would depend on file size. Since we support segmentation, file size here is smaller and standard to every segment. Now we should be worrying about amount of time server takes to deliver the media file. To avoid network congestion caused by HTTP streaming we propose newer and faster streaming mechanisms like RTSP or mms. That way response time can be reduced.
4/21/2019
Architecture of Multimedia Digital

8. Architecture of Multimedia Digital Library@2006
Scalability
Addressing by Stripping
Request Load
Data Size
Simultaneous Connections
On Demand Unicasting
High Bandwidth to increase number of connections.
Average stream rate
Factors influencing scalability are request load, data size, number of simultaneous connections, bandwidth. We address data size and request load through stripping. For number of simultaneous connections we propose an on demand unicasting (file download, multi/broad casting are not a feasible options). So number of simultaneous connections depends on Maximum bandwidth/average stream rate. So we recommend such libraries to have higher bandwidth to address large number of audience.
4/21/2019
Architecture of Multimedia Digital

9. Components in architecture
Application Controller
Segmentation Engine
Media Server
Data Store
Media Search and Index Module
Metadata server
Once the performance and scalability of the application are addressed at design level. An architectual frame work would have following components. Application Controller, segmentation engine, media server, data store, media search and index component, metadata server. Lets take a look at each of these components.
4/21/2019
Architecture of Multimedia Digital

10. Application Controller
Media Submission Manager
Media Player Interface
Media Encoder
Digital Library Manager
An application controller would have media submission manager, digital library manager, media player interface, media encoder. Media submission module would help users to upload media files through web based or offline application. Player Module is an interface for client end web based/offline player which supports simultaneous buffering. Media encoder converts the submitted files into format required by us.
4/21/2019
Architecture of Multimedia Digital

11. Architecture of Multimedia Digital Library@2006
Segmentation Engine
Synchronizer
Meta Data Generator
Stripper
Segmentation engine contains stripper, meta data generator, synchronizer. Stripper helps in cutting the media file into smaller segments, meta data for each of these segments would be added by meta data generator. Synchronizer helps submission module and player module for smooth transactions.
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Architecture of Multimedia Digital

12. Architecture of Multimedia Digital Library@2006
Media Server
Alternative Streaming Protocols
On demand Unicasting
Media Server would help us deliver content through multiple protocols. Using on demand unicasting.
4/21/2019
Architecture of Multimedia Digital

13. Putting it all together in the Architectural Framework
A solution that provides the architectural elements for addressing the performance and scalability issues
Major Components
Application Controller
Media uploading
Media Retrieval
Media Player and Encoder
Concurrent and Simultaneous Request Handlers
Segmentation Engine
Synchronizer
Metadata Generator
Striper
Transcription Tool
Putting it all together. A solution that provides the architectual elements for addressing performance and scalability of multi media digital library.
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Architecture of Multimedia Digital

14. Architectural Framework
Divided into search and index module, application controller, segmentation engine, meta data server, media server and media store.
Application controller may contain modules and front end applications like player module, media encoder, submission module,

15. Strengths and Weaknesses of the Architectural Framework
Performance and scalability addressed at design level.
Implementation of Architecture is applicable in any Technological Frameworks like J2EE, .NET etc.
Weaknesses
Transcription of the media files is unreliable due to segmentation.
Through this architecture
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Architecture of Multimedia Digital

16. Conclusion and Future Work
Applications
Educational Institutions
Research
Future Work
Open Source Realization of Framework
Applying the framework to a particular domain
To conclude Multimedia digital libraries are the future of all digital libraries, will be of great use to educational institutions and researchers.
4/21/2019
Architecture of Multimedia Digital