7Techniques of Mirroring Website Mirrors:Mirrors simply compare and pull the contentsfrom a single master web site at a regularintervals and make identical contentsavailable on another computer, ideally closerto the users making use of it.
8Motives for Mirroring Load Balancing - yahoo.co.uk yahoo.co.in High Availability - ADS mirrorsMultilingual replication -Database Sharing –Franchise / Local Versions -quicken.excite.com quicken.comVirtual Hosting - sports.catalogue.com
9Mirroring IssuesMaintenance of mirror-sites in different geographical locations.Integrity of the mirrored contentsProviding Host-Independent URLS.Initial transfer of dataOptimizationEconomical constraintsProviding Efficient routing
11Mirroring Experience IUCAA (Inter University Centre For Astronomy and Astrophysics)works closely with ERNET(Educational and ResearchNETwork) to make thisnetwork a content orientednetworkhttp://www.iucaa.ernet.in/
12ERNET India ? In 1986, then Department of Electronics had initiated a project "ERNET" with thefunding from UNDP. The objective was toestablish and operate a nationwideInternet for the Indian academic andresearch community. Now it has becomea full pledged ISP known as ERNET India.
20Mirror-site under construction Chandra Data Archive (CDA)424 GB data is available through ftp service. ftp://cdaftp.iucaa.ernet.inIncremental update is being done regularly.Web based CDA service will be provided,once the new release of CXCDS softwareis made available.
21Acknowledgement Dr. Francois Ochsenbein - VizieR Dr. Guenther Eichhorn and Dr.Alberto Accomazzi - ADSDr. Ramadurai Padmanabhan - CDA