Please wait, while we are loading the content...
Please wait, while we are loading the content...
| Content Provider | ACM Digital Library |
|---|---|
| Author | Verbin, Elad Zur, Tal Milo, Tova |
| Abstract | We consider in this paper a class of Publish-Subscribe (pub-sub) systems called topic-based systems, where users subscribe to topics and are notified on events that belong to those subscribed topics. With the recent flourishing of RSS news syndication, these systems are regaining popularity and are raising new challenging problems. In most of the modern topics-based systems, the events in each topic are delivered to the subscribers via a supporting, distributed, data structure (typically a multicast tree). Since peers in the network may come and go frequently, this supporting structure must be continuously maintained so that "holes" do not disrupt the events delivery. The dissemination of events in each topic thus incurs two main costs: (1) the actual transmission cost for the topic events,and (2) the maintenance cost for its supporting structure. This maintenance overhead becomes particularly dominating when a pub-sub system supports a large number of topics with moderate event frequency; a typical scenario in nowadays news syndication scene. The goal of this paper is to devise a method for reducing this maintenance overhead to the minimum. Our aim is not to invent yet another topic-based pub-sub system, but rather to develop a generic technique for better utilization of existing platforms. Our solution is based on a novel distributed clustering algorithm that utilizes correlations between user subscriptions to dynamically group topics together, into virtual topics (called topic-clusters), andt hereby unifies their supporting structures and reduces costs. Our technique continuously adapts the topic-clusters and the user subscriptions to the system state, and incurs only very minimal overhead. We have implemented our solution in the Tamara pub-sub system. Our experimental study shows this approach to be extremely effective, improving the performance by an order of magnitude. |
| Starting Page | 749 |
| Ending Page | 760 |
| Page Count | 12 |
| File Format | |
| ISBN | 9781595936868 |
| DOI | 10.1145/1247480.1247563 |
| Language | English |
| Publisher | Association for Computing Machinery (ACM) |
| Publisher Date | 2007-06-11 |
| Publisher Place | New York |
| Access Restriction | Subscribed |
| Subject Keyword | Publish-subscribe Peer-to-peer Dynamic clustering |
| Content Type | Text |
| Resource Type | Article |
National Digital Library of India (NDLI) is a virtual repository of learning resources which is not just a repository with search/browse facilities but provides a host of services for the learner community. It is sponsored and mentored by Ministry of Education, Government of India, through its National Mission on Education through Information and Communication Technology (NMEICT). Filtered and federated searching is employed to facilitate focused searching so that learners can find the right resource with least effort and in minimum time. NDLI provides user group-specific services such as Examination Preparatory for School and College students and job aspirants. Services for Researchers and general learners are also provided. NDLI is designed to hold content of any language and provides interface support for 10 most widely used Indian languages. It is built to provide support for all academic levels including researchers and life-long learners, all disciplines, all popular forms of access devices and differently-abled learners. It is designed to enable people to learn and prepare from best practices from all over the world and to facilitate researchers to perform inter-linked exploration from multiple sources. It is developed, operated and maintained from Indian Institute of Technology Kharagpur.
Learn more about this project from here.
NDLI is a conglomeration of freely available or institutionally contributed or donated or publisher managed contents. Almost all these contents are hosted and accessed from respective sources. The responsibility for authenticity, relevance, completeness, accuracy, reliability and suitability of these contents rests with the respective organization and NDLI has no responsibility or liability for these. Every effort is made to keep the NDLI portal up and running smoothly unless there are some unavoidable technical issues.
Ministry of Education, through its National Mission on Education through Information and Communication Technology (NMEICT), has sponsored and funded the National Digital Library of India (NDLI) project.
| Sl. | Authority | Responsibilities | Communication Details |
|---|---|---|---|
| 1 | Ministry of Education (GoI), Department of Higher Education |
Sanctioning Authority | https://www.education.gov.in/ict-initiatives |
| 2 | Indian Institute of Technology Kharagpur | Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project | https://www.iitkgp.ac.in |
| 3 | National Digital Library of India Office, Indian Institute of Technology Kharagpur | The administrative and infrastructural headquarters of the project | Dr. B. Sutradhar bsutra@ndl.gov.in |
| 4 | Project PI / Joint PI | Principal Investigator and Joint Principal Investigators of the project |
Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon |
| 5 | Website/Portal (Helpdesk) | Queries regarding NDLI and its services | support@ndl.gov.in |
| 6 | Contents and Copyright Issues | Queries related to content curation and copyright issues | content@ndl.gov.in |
| 7 | National Digital Library of India Club (NDLI Club) | Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach | clubsupport@ndl.gov.in |
| 8 | Digital Preservation Centre (DPC) | Assistance with digitizing and archiving copyright-free printed books | dpc@ndl.gov.in |
| 9 | IDR Setup or Support | Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops | idr@ndl.gov.in |
|
Loading...
|