GIS Web Services. Acknowledgement: Thanks to Principal & Dr. (Mrs.) G.V. Rao, CRS-GIS, K.J.

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1 GIS Web Services Presented By: Shivani Shukla Acknowledgement: Thanks to Principal & Dr. (Mrs.) G.V. Rao, CRS-GIS, K.J. Somaiya College Of Science & Commerce, Mumbai for the inspiration of poster making. Thanks to Cybertech Systems & Software Ltd. sharing their knowledge and being supportive. Thanks to IIT Geomatrix Committee for giving this opportunity. Introduction: Geographical Information Systems (GIS) play a significant role in the analysis of data, production of output and in the decision making process. In the simplest terms, GIS provides us the means to visualize information that better allows us to solve significant problems related to (real earth dynamics) our world. GIS Web Services have the potential to revolutionize the way in which GIS is developed, accessed and used. GIS web services provide spatial data or functionality on the World Wide Web (www). GIS services applications use both spatial and non-spatial data and perform basic geoprocessing task such as: Address Finder Spatial Queries (Point, Lines and Polygons) Routing/ Route Finder Mapping Wireless Locations GIS web services make it easier to share geographic data and to integrate other technologies with GIS. For instance, Geospatial-Intelligence: GIS integration with CCTV Cameras. GIS web services make it possible for user to access GIS data and functionality through the web and to integrate them with their own systems and applications without the need to develop or host specific GIS tools and data sets by themselves. These services provides user-friendly interface for many applications which use geographic data, such as - 1 -

2 Land-Records Management, Urban Planning, tourism, vehicle guidance and navigation, and e-commerce. GIS web services enable application developers to integrate GIS functionality into their web applications without having to build the functionality or host the mapping data locally. Since GIS deals with large volume of data, so it is of utmost importance to check whether data provided to the user from a web service is giving the desired result. So this can only be done with help of testing the service usability. Testing is performed in order to enhance the functionality of the GIS Web Services. Performance testing is testing that is performed, from one perspective, to determine how fast some aspect of a system performs under a particular workload. Data are of sensitive nature and are required in every organization and day to-day life. Therefore, GIS web services take a challenge to provide image service and feature service. Performance testing can serve different purposes. It can demonstrate that the system meets performance criteria. It can compare two systems to find which performs better or it can measure which parts of the system or workload cause the system to perform badly. Thus, performance defect is detected, which helps to remove the obligations. GIS Web Services makes a reality the vision of creating a platform independent distribution channel for GIS data. Applications can share data from different data sources and formats and have them combined in a single application, without it being apparent that data has come from different sources or locations. Thus, GIS Web Services has provided a new way of working with GIS

3 Methodology: This study is intended to implement the working of GIS Web Services. To explain this, system approach is adopted. First it addresses to consider how web services work in geographic information system and what kind of platforms and technologies of the GIS Web services are needed and how the users access these services. It also takes into consideration of accessing huge spatial data. Fig. 1, illustrates the interaction between client and server and also between sending request and receiving response. Fig. 1: Different Users Of GIS Web Services 1. Working of web services in GIS - GIS Web services enable application developers to integrate GIS functionality into their Web applications without having to build the functionality or host the mapping data locally. As web services have following features - Web services are application components Web services communicate using open protocols Web services are self-contained and self-describing Web services can be discovered using UDDI - 3 -

4 Web services can be used by other applications XML is the basis for Web services Presented By: Shivani Shukla GIS Web services are Internet applications that use data and related functionality to perform basic geoprocessing tasks. 2. Platform required Application Programming Interface defines how to access a software-based service. An API is a published specification that describes how other software programs can access the functions of an automated service. It is a source code interface that a computer system or program library provides to support requests for services to be made of it by a computer program. An API differs from an application binary interface in that it is specified in terms of a programming language that can be compiled when an application is built, rather than an explicit low level description of how data is laid out in memory. Thus, Web API is the evolution of the scripts that were common with most early GIS systems. An application programming interface is a set of subroutines (organized as object oriented programming) designed to perform a specific task. GIS API's are designed to manage GIS data for its delivery to a web browser client from a GIS server. These are accessed with commonly used scripting language such as VBA or JavaScript. These are used to build a server system for the delivery of GIS that is to made available over an intranet or publicly over the Internet. 3. Technologies used SOAP (Simple Object Access Protocol) is a protocol for exchanging XML-based messages over computer networks, normally using HTTP. SOAP forms the foundation layer of the Web services stack, providing a basic messaging - 4 -

5 framework that more abstract layers can build on. SOAP is a lightweight protocol for exchanging structured information in a decentralized, distributed environment. It is an XML based protocol that consists of three parts: an envelope that defines a framework for describing what is in a message and how to process it, a set of encoding rules for expressing instances of application-defined datatypes, and a convention for representing remote procedure calls and responses. computers to communicate independently of an operating system or platform by using HTTP and XML. SOAP toolkit easily communicate with GIS Web Services in languages like Java,.NET, or ColdFusion. It is necessary to get an authentication for accessing these services and for the WSDL location. The toolkits also provides the available methods, parameters, and parameter types for each service. Web Services Description Language (WSDL) is an XML document that describes a set of SOAP messages and how those messages are exchanged. It is an XML file that contains details of available operations, execution endpoints and expected SOAP request-response structures. These concepts work under the framework of SOA Architecture, as represented in the Fig. 2. Fig. 2: SOA Service Oriented Architecture - 5 -

6 4. How user can access these services- To access web service we need to become authenticated user. The Fig. 3, illustrates the architecture which is applicable for any GIS Web Services. Fig. 3: In General, GIS Web Services Architecture 5. Interaction between client and server and also between sending request and receiving response - Web Services are the applications that run on a Web Server and communicate with other applications. It uses a series of protocols to respond to different requests. Results: GIS Web Services make a reality the vision of creating a platform independent distribution channel for GIS data. Applications can share data from different data sources and formats and have them combined in a single application, without it being apparent that data has come from different sources or locations. GIS Web Services are now - 6 -

7 advancing into the form of Online GIS Services which will be more informative for the world by adding more and more availability can be ensured. Conclusion: GIS Web Services are self-contained application components that provide commercial businesses and government organizations to easily integrate mapping, GIS functionality, and geographic content into custom Web-enabled applications. Users can be anywhere in the world and with a simple browser can make requests and receive desired spatial results. GIS Web Services facilitates in mapping functionality and GIS content into browser, desktop, mobile, and server applications. References: An Article in a Journal Francisco Juli, User Interface For The Integration Of Gis Components Page No Web Pages: