GeoSpatial Technologies and Web Applications M. Arulraj Sci/Engr – SF Manager, Bhuvan Web Services Development [email protected] GIS Activities in Problem Solving Environment Empowering Human Take to Activities Action Plan Complex Data Modeling Analyze Interactive Mapping Integration Measure Observe Visualization Modeling . Application of this science is multi-disciplinary Major Components of GIS and Role of open source s/w Data Creations Vector, Raster & attribute Data organizations & Management Complete GIS Data query, processing, Solutions analysis and modeling Data presentations and visualizations OpenLayers Data sharing and disseminations Tools and technologies • Quantum GIS • Open Jump • SAGA, MapWindow GIS • OpenLayer API Desktop GIS • Mapfish, • Geoeditor, • GRASS Geoweb Remote • Geexplorer • OSIM 2.0 Sensing • SAGA • Geonetwork Catalogue Statistical Server • R Geo-spatial DomainGn Geo- GPS • Gpsbabel RDBMS • POSTGIS+ POSTGRESQL • Gpsdrive • TerrLib GIS s/w GIS Servers developme nt • GDAL/OGR • Osgeo MapServer • Geotool • Geoserver • OpenLayer API What is open source? Open source software is software where the source code is made available under a license that allows the modification, and re-distribution of the software at will. The distribution terms of open-source software must comply with the following criteria: Free redistribution; Source code; Derived works; Integrity of the author's source code; No discrimination against persons or groups; No discrimination against fields of endeavor; Distribution of license; License must not be specific to a product; License must not restrict other software; License must be technology-neutral. What is open source? 1. Free Redistribution The license shall not restrict any party from selling or giving away the software as a component of an aggregate software distribution containing programs from several different sources. The license shall not require a royalty or other fee for such sale. 2. Source Code The program must include source code, and must allow distribution in source code as well as compiled form. Where some form of a product is not distributed with source code, there must be a well-publicized means of obtaining the source code for no more than a reasonable reproduction cost preferably, downloading via the Internet without charge. 3. Derived Works The license must allow modifications and derived works, and must allow them to be distributed under the same terms as the license of the original software. 4. Integrity of The Author's Source Code The license may restrict source-code from being distributed in modified form only if the license allows the distribution of "patch files" with the source code for the purpose of modifying the program at build time. The license must explicitly permit distribution of software built from modified source code. The license may require derived works to carry a different name or version number from the original software. 5. No Discrimination Against Persons or Groups The license must not discriminate against any person or group of persons. What is open source? 6. No Discrimination Against Fields of Endeavor The license must not restrict anyone from making use of the program in a specific field of endeavor. For example, it may not restrict the program from being used in a business, or from being used for genetic research. 7. Distribution of License The rights attached to the program must apply to all to whom the program is redistributed without the need for execution of an additional license by those parties. 8. License Must Not Be Specific to a Product The rights attached to the program must not depend on the program's being part of a particular software distribution. If the program is extracted from that distribution and used or distributed within the terms of the program's license, all parties to whom the program is redistributed should have the same rights as those that are granted in conjunction with the original software distribution. 9. License Must Not Restrict Other Software The license must not place restrictions on other software that is distributed along with the licensed software. For example, the license must not insist that all other programs distributed on the same medium must be open-source software. 10. License Must Be Technology-Neutral No provision of the license may be predicated on any individual technology or style of interface. OGC – Open Geospatial Consortium • International Standards organisation working towards the development of publicly available interface standards. • Founded in 1994 • Four Operational Programs • Standards Programs • Interoperability Programs • Communication and Outreach Program • Compliance Program OGC – Open Geospatial Consortium • Standards Programs • Rules and guidelines, aimed at the optimum degree of interoperability • 46 OGC standards at present including WMS, WFS, WCS, GML, KML, City GML, Open LS etc. • Interoperability Programs • Capability – common set of business procedure, read and write same file format, using same protocols • 85 initiatives to speed up the development and usage of interoperability concepts • Communication and Outreach Program • Adoption, Implementation of OGC standards, Development and supporting regional and sectoral programmes. • Compliance Program • Free web testing facility to certificate and lively harmonisation of a lively group of developers. What is web service? A 'Web service' (also Web Service) is defined by the W3C as "a software system designed to support interoperable machine-to-machine interaction over a network". Web services allows us to build a highly distributed infrastructure. Each web services can be dedicated to a specific task. The web service concept defines the relationships between the three major actions in geo-spatial data access: Service providers who publish services; Service requestor who search and use services; The service registry that matches the request with the existing services. XML The Extensible Markup Language (XML) is a general-purpose specification for creating custom markup languages. It is classified as an extensible language because it allows its users to define their own elements. Its primary purpose is to facilitate the sharing of structured data across different information systems, particularly via the Internet, and it is used both to encode documents and to serialize data. It started as a simplified subset of the Standard Generalized Markup Language (SGML), and is designed to be relatively human-legible. By adding semantic constraints, application languages can be implemented in XML. These include XHTML, MathML, GraphML, Scalable Vector Graphics, MusicXML, and thousands of others. Moreover, XML is sometimes used as the specification language for such application languages. XML is recommended by the World Wide Web Consortium (W3C). It is a fee-free open standard. The recommendation specifies both the lexical grammar and the requirements for parsing. OGC Web Services (OWS) Initiatives • OGC has started a series of web-based interoperability initiatives since 1999. • The purpose of those initiatives is to develop a set of draft interoperability specifications for considering as official OGC specifications. – Web feature services specification (WFS) – Web coverage services specification (WCS) – Web map services specification (WMS) – Web registries services specification (WRS) Web Coverage Services (WCS) Specification • OGC Web Coverage Services Specification defines the interfaces between web-based clients and servers for accessing on-line multi- dimensional geospatial data in an interoperable way. – For raster(grid) data and multi-dimensional remote sensing imagery (e.g., multiple bands, time-series, etc) Get Capabilities Describe Coverage Get Coverage Web Feature Services (WFS) Specifications • OGC Web Feature Services Specification defines the interfaces between web-based clients and servers for accessing feature-based geosptial data (basic,Xlink,Transaction) – Vector data, such as road network, political boundary, cadastral data, river, coastal lines, etc. Get Capabilities Get GML object Describe Feature Type Transaction Get Feature LockFeature Web Map Services Specification • WMS, which filters and portrays spatial data to return static maps (rendered as pictures by the server). (Basic,Queryable) • It is one of the most widely implemented OGC specifications. Get capabilities Get map Get featureinfo Web Catalogue Services Specification (CSW) • Web Registries Services Specification defines the interfaces between web-based clients and servers for finding the required data or services from the registries. • Originally, the WRS was called Catalog Interoperability Specification (State-less). Geo-Information System- Simple Architecture External and Internal data Data Management Model Management Spatial model & Spatial & Major Components Attribute Non-spatial data Non-spatial model data • Database Server- Knowledge Database Management Management • Application server- Application software Object • Hardware data Dialog Management Attribute base query and report Spatial query and spatial output Spatial data Decision maker Information system Desktop GIS- General Architecture User GIS Applications GIS Data What is Web GIS ? The integration of GIS and Internet technologies is allowing GIS professionals to solve one of the most important problems inhibiting information utility: How to provide access to information and data without burdening end users with complicated and expensive software. Internet