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6th October 2005 JISC (Geo)-Interoperability Project GWG 06092005 James Reid GeoServices, EDINA 1 Overview Background and rationale o o o o Who? What? Why? How? Demo Issues Conclusions Recommendations and discussion 2 Who ? (as unfunded partner and data provider) 3 What is ‘Interoperability’ ? “The ability of software and hardware on multiple machines from multiple vendors to communicate. “ (The Free On-line Dictionary of Computing) “The ability of a system or a product to work with other systems or products without special effort on the part of the customer.” (whatis.com) Products achieve interoperability with other products using either or both of two approaches: By adhering to published interface standards By making use of a "broker" of services that can convert one product's interface into another product's interface "on the fly" A good example of the first approach is the set of standards that have been developed for the World Wide Web. These standards include TCP/IP, Hypertext Transfer Protocol, and HTML. The second kind of interoperability approach is exemplified by the Common Object Request Broker Architecture (CORBA) and its Object Request Broker (ORB). In the world of (geo)-interoperability, the favoured approach has been to move towards adopting interface standards. 4 Remote access via web services University College, London Demis, Netherlands Globe, Colorado MIMAS, Manchester GeoData GeoData GeoData EDINA, Edinburgh GeoData Web Services Web Services Web Services Web Services GeoData IONIC, Belgium Web Services GeoData Web Services Metadata Maps Data 5 Interoperability and the JISC IE JISC 5 year strategy: “an on-line information environment providing secure and convenient access to a comprehensive collection of scholarly and educational material” It is recognised that interoperability is of fundamental importance and that the JISC IE is a component of the national and global networked environment 6 Interoperability and the JISC IE To date, there has been no formal geospatial interoperability study between the national data centres, or between the national data centres and users in institutions. This work is required as: there is a need to understand how the UK academic sector can best exploit developments in the standards underpinning these developments. greater understanding is required of what is involved in supporting research and education in this important area in the future. Hence this project…. 7 Why ‘Interoperability’? Increases the value of existing and future investments in Information Systems. Allows portability of data. Expands choices for vendor alternatives – no vendor lock-in. Enables vertical industry segments to unify trading practices. Decreases the long-term cost of ownership for applicable software investments. Enables leverage of existing skill-sets, i.e., does not require proprietary training. Provides a benchmark for software design. 8 Why? - A view from the bunker… "I'd like to see an [OS maps] API to rival Google, … that the API will be published as an open standard and so not subject to arbitrary change, and that it will be made available to all. Open standards may evolve more slowly but they are reliable and can't be changed simply because the commercial priorities of their owners have shifted. These open interfaces are the key to the next stage of the internet's evolution, just as they have been the driving force behind its development to date. It doesn't matter whether the program at the other end is a simple terminal emulator or the interface to a massively sophisticated mapping system - once the interface is published it can be used. “ Bill Thompson, Technical Analyst http://news.bbc.co.uk/1/hi/technology/4640893.stm 9 How - OGC Specifications (some!!) Web Map Service (WMS) Specifies the behavior of services that return georeferenced maps Web Feature Service (WFS) Interface that supports query level access to vector data repositories Web Coverage Service (WCS) Supports networked interchange of geospatial data as ‘coverages’ containing values or properties of geographic locations 10 How – In more Detail… Lets look at the most popular standard – WMS - in more detail… 11 How - Web Map Server Specification 1.1.1 Specification defines syntax for URLs to invoke map operations. XML encoding defined for service level metadata. GetCapabilities GetMap Returns server-level metadata, description of services and content, acceptable request parameters Returns map image whose geospatial and dimensional parameters are well-defined GetFeatureInfo Returns information about particular features shown on map (optional) 12 How - WMS Interface: Operation GetCapabilities Web Map Service Capabilities XML Document with Layer Information GetMap Client Rendered Map Image GetFeatureInfo Returns info about feature Legend Roads Water Buildings Map Layers Adapted from Web Map Server Demonstration presentation © 2000 OGC 13 How – Images vs Data Image Services Deliver image only (snapshot of the data), not actual feature (vector) data More limited functionality—can’t export locally; changing symbology more limited Lower bandwidth requirement Feature (data) Services Streams actual feature data over the Internet, available as individual feature classes Allows extra functionality of changing symbology or exporting the data locally; cleaner maps Higher bandwidth requirement Filtering; more sophisticated linking 14 Back to the project! Specific Project aims: to prove the feasibility of delivering geo-spatial data using OGC standards; to demonstrate ease of use and added value; to build support and enthusiasm for further development; to stimulate and advance further thinking; and to identify major hurdles in full development. 15 Project Outputs A range of OGC based web services (WMS; WFS; WCS) A basic annotation web service (based on OGC XIMA specification) A series of demonstrator clients to illustrate: Access to data (see demo) A teaching focussed use case (urban expansion) A research focussed use case (based on dynamic image registration using web services) A report on the utility and issues surrounding implementation of open standards for geospatial data within the JISC IE, including an assessment of security and access authorisation issues 16 Demo… Project website 17 Issues • Security • Scalability • Technical implementation • Metadata 18 Conclusions • Use of open standards is: – (relatively) easily achievable – desirable (discuss!) • A number of practical issues need to be addressed before wider adoption • There are both internal and external drivers within JISC IIE that may push towards adoption “A service-oriented framework provides significant benefits to stakeholders including policy makers, managers, institutions, suppliers and developers and is a business driven approach for developing ICT infrastructures that encourages innovation by being agile and adaptive.” (Statement of Principles, e-Framework Overview, July 2005) 19 Recommendations [FOR DISCUSSION] a further Interoperability Pilot in order to establish the basis of a Web Registry for UK academia’s geospatial resources be conducted. The objectives of any potential follow on project(s) should be to consolidate and further nurture the OGC services developed as part of this project and to exploit (investigate?) these within a service oriented infrastructure by embedding within other JISC services. a specific working group (perhaps the Grid GIS Working Group) be tasked with investigating web services security issues and that workshops (incorporating the ongoing JISC funded work on Shibboleth) be convened in order to establish best practice and to recommend a road map for addressing security and geoDRM aspects of geospatial interoperability within the UK academic community. investigations into the issue of service scalability and resilience via a funded programme of stress testing and exploration of alternative service architectures (hardware and software mixes) be undertaken in order to establish whether the e-Framework service oriented approach is a sustainable approach for the delivery of geospatial resources. ongoing (financial) support to the existing Interoperability partners is made in order to maintain and diversify the range of services they can support and make available via interoperable means. JISC with the assistance of the JISC GWG needs to come up with a strategy to take this forward with funding commitment for services from JISC. 20 21 A ‘traditional’ online service A Web Services based Service (ie OGC like) Via a Repository (ies) WAAS Client WMS Service ? WMS Service Proprietary Service WAAS Service WFS Service GeoData GeoData GeoData EDINA National Data Centre Research Council Institute Data set 1 Data set 2 National Data Centre