® Reference Architecture and Agile Development George Percivall OGC Chief Engineer 4 April 2014 Copyright © 2014, Open Geospatial Consortium

OGC ® Reference Architecture Standards IEEE 1471 –General process. Requires viewpoints but does not define any. RM-ODP –Reference Model for Open Distributed Processing –Enterprise, Informational, Computational, Engineering, Technology –Viewpoint languages coordination with UML OASIS Reference Model for Service Oriented Architecture –Focused on Services Others: DODAF, TOGAF, Zachman Copyright © 2014, Open Geospatial Consortium

OGC ® SUMMARY OF ARCHITECTURE STANDARDS Copyright © 2014, Open Geospatial Consortium

OGC ® RM-ODP Reference Architecture Viewpoints Information Viewpoint Computational Viewpoint Engineering Viewpoint Implementation/Development Viewpoints in “Reference Model - Open Distributed Processing (RM-ODP)” ISO/IEC Technology Viewpoint Enterprise Viewpoint Community Objectives Business aspects: purpose, scope and policies What for? Why? Who? When? Information sources and models What is it about? Types of services and protocols How does it work? Solution types: distribution infrastructure How do the components work together? Implementation system: hardware, software, distribution With what? Abstract/Design Copyright © 2014, Open Geospatial Consortium

OGC ® Department of Defense (DoD) Architecture Framework (DoDAF) Copyright © 2014, Open Geospatial Consortium High-Level Operational Concept Graphic (OV-1) Operational Activity Model (OV-5). To-Be Operational Activity to Systems\Function Traceability Matrix (SV-5) Systems Interface Description (SV-1) Logical Data Model (OV-7), Systems Data Exchange Matrix (SV-6): Technical Standards Profile (TV-1) Systems Communications Description (SV-2) Physical Schema (SV-11) Systems Functionality Description (SV-4)

OGC ® DODAF Operational Activity Model (OV-5). Examples from DoDAF 1.5 Volume 2 DoDAF 1.5 Volume 2DoDAF 1.5 Volume 2 Copyright © 2014, Open Geospatial Consortium

OGC ® Comparison of Architecture Artifacts Copyright © 2014, Open Geospatial Consortium RM-ODPGEOSSDODAF Enterprise Summary diagram Scenarios Information Abstract specifications Computational Services Engineering Component Types Use Cases including components Scenario to Use Case matrix Services to Components Communications Technical Component Instances IP addresses High-Level Operational Concept Graphic (OV-1) Operational Activity Model (OV-5). To-Be Operational Activity to Systems\Function Traceability Matrix (SV-5) Systems Interface Description (SV-1) Logical Data Model (OV-7), Systems Communications Description (SV-2) Physical Schema (SV-11) Systems Functionality Description (SV-4) Technical Standards Profile (TV-1) Systems Data Exchange Matrix (SV-6):

OGC ® Geosciences Reference Architecture examples GEOSS Architecture Implementation Pilot –System of Systems based on Interoperability Arrangements –Process of iterative development while refining an architecture –AIP Architecture using RM-ODP – _aip7_architecture.pdfhttp:// _aip7_architecture.pdf ENVRI –Common Operations of Environmental Research Infrastructures –ENVRI Reference Model V1.1 – Copyright © 2014, Open Geospatial Consortium

Information Viewpoint Computational Viewpoint Engineering Viewpoint Optimized Design/Development Technology Viewpoint Enterprise Viewpoint Community Objectives GEOSS Vision and Targets Societal Benefit Areas System of Systems/ Interoperability Abstract/Best Practices GEOSS AIP Architecture RM-ODP Viewpoints Earth Observations Geographic Features Spatial Referencing Metadata and Quality GEOSS Data-CORE Catalog/Registry Access and Order Processing Services Sensor Web User Identity Component Types Information Framework Use Cases Services Tutorials

OGC ® ENVRI Reference Model V1.1 A reference model is not a reference architecture. –A reference architecture is an architectural design pattern indicating an abstract solution that implements the concepts and relationships identified in the reference model [8]. –Different from a reference architecture, a reference model is independent from specific standards, technologies, implementations or other concrete details. A reference model can drive the development of a reference architecture or more than one of them [9]. The ENVRI Reference Model is structured according to the Open Distributed Processing (ODP) standard. –As such, the Reference Model is defined from five different perspectives. In the context of ENVRI, which uses ODP to define an 'archetypical' environmental research infrastructure rather than a specific (implemented) infrastructure, –three viewpoints take particular priority – the Science, Information and Computational viewpoints: –The remaining two viewpoints (Engineering and Technology) are more relevant to specific instances of research infrastructure. Nevertheless, the ENVRI Reference Model will address these viewpoints to some extent in future revisions. Copyright © 2014, Open Geospatial Consortium

OGC ® Prototyping Versus Specifying “Prototyping Versus Specifying: A Multiproject Experiment” 1) Prototyping yielded products with roughly equivalent performance, but with about 40 percent less code and 45 percent less effort. 2) The prototyped products rated some what lower on functionality and robustness, but higher on ease of use and ease of learning. 3) Specifying produce produced more coherent designs and software that was easier to integrate. –BARRY W. BOEHM, TERENCE E. GRAY, AND THOMAS SEEWALDT, IEEE TRANSACTIONS ON SOFTWARE ENGINEERING, VOL. SE-10,NO. 3,MAY 1984 See also Michael Schrage, e.g., Serious Play and “Cultures of Prototyping” in Bringing Design to Software Copyright © 2014, Open Geospatial Consortium

OGC ® Agility and Architecture Use agile development to get to a good architecture by appropriately applying suitable combinations of –architectural functions (such as communication, quality attributes, and design patterns) and –architectural skills at four points in the development life cycle. (up-front planning, storyboarding, sprint, and working software) w/homepage/2010/0410/T_SW_AgileArchitectureInteractio ns.pdf Copyright © 2014, Open Geospatial Consortium

OGC ® IEEE SOFTWARE - March/April 2010 Copyright © 2014, Open Geospatial Consortium

OGC ® David Byrne: How Architecture helped music evolve He asks: Does the venue make the music? –From outdoor drumming to Wagnerian operas to arena rock, Byrne explores how context has pushed musical innovation. Model for creation (at 13:45 in talk) –We make music primarily in a form to fit the context and we make art to fit museum walls –We write software to fit existing operating systems. Its evolutionary, its adaptive. –This is a reverse view from the traditional romantic view: first comes the outpouring of emotion and then somehow it gets shaped into something. –The passion is still there, but the vessel that it is going to be injected into and poured in to is instinctively and intuitively created first. Copyright © 2014, Open Geospatial Consortium