Geospatial Systems Architecture Todd Bacastow

Views of a System Architecture Enterprise Information Computational Engineering Technology

What is an architecture? A system architecture is the conceptual design that defines the structure and/or behavior of a system There is no universally agreed definition Systems architecture can best be thought of as a representation Maybe expressed in hardware, software, or organizational management It is also a process because a sequence of steps It can also be a discipline

Geospatial architecture Geospatial architecture is a strategic blueprint Broadly, geospatial architecture effort addresses the following views: –business activities and processes, –data sets and information flows, and –services.

Analogies Consider a community that maintains an infrastructure for a public service to homes and businesses. This infrastructure might include: –Electricity producers –Drinking water purification and distribution –Sewage treatment –Other waste disposal –Natural gas distribution –Public transport –Cable television and telephones –Roads and toll ways

GIS Enterprise Evolution Peters, Fig 2-1

GIS Department Peters, Fig 2-2

Organizational GIS Peters, Fig 2-3

Community GIS Peters, Fig 2-4

Web Peters, Fig 2-8

Mobile Peters, Fig 2-9

Modes of Deployment Peters, Fig 2-11

Federated Technology Peters, Fig 2-12

System Architecture Design Peters, Fig 1-1

Number of Users Cost Internet Viewer Component Hand-held Desktop Professional Functionality GIS Software Classification

GIS Market

ArcSDE Unifies Spatial Data Access ArcGIS Desktop Applications ArcGIS Desktop Applications ArcIMS, ArcExplorer, ArcPad ArcIMS, ArcExplorer, ArcPad MapObjects MapObjects Third-Party applications Third-Party applications SQL Server OracleInformix IBM DB2 ArcSDE Services

Enterprise GIS Organizations expect to... Leverage existing spatial data (eliminate silos) Integrate spatial data with core business data Incorporate spatial into workflow between departments (for a city…tax assessor, appraisal, DPW, police, fire, IT) Deploy IT standards to all their data Move client / server GIS apps to the web and wireless devices Benefit from scalability and security

First, Spatially Enable The Data… ArcSDE Data Is Independent of Application ArcIMSArcGIS SQL Server High Availability, High Performance, Secure, Scalable

Next, publish the informationArcReader A New Extension Publisher ArcMap Data MXD PMF

How? Distributed GIS Consume and expose Web services for: –Mapping –Metadata –Data sharing and distribution –Geoprocessing Provide standard services and components for web developer (.Net, “generic XML/SOAP”, or Java API’s)

GIS Internet Enterprise Web Server Databases Broker Browsers Web Applications

Emerging GIS Internet Enterprise Web Server Databases Broker Browsers Web Applications Services

Distributed GIS Development New Concept – g.net architecture –leveraging emerging web technologies Web services –GIS technology for applications over the web Mapping Metadata GIS Functionality –Spatial Data sharing and distribution Extends ArcGIS System concept –Desktop Applications –Back Office Servers –Distributed “Services” via the Internet

G.net Architecture Building Blocks GIS Portal Network architecture (Distributed) Loosely Coupled Internet Standards Many GeoServices Many Clients Metadata Servers Open / Interoperable Full GIS capabilities GIS Users GIS Portal Metadata Server Search Catalog and Find  Publish GIS Data & Services  Document in Catalog Connect and Use Checkout and Use World Wide Web Author, Manage, Serve Geographic Information Collections Author, Manage, Serve Catalogs

“Software for G.Net” GIS Clients GIS Web Services ArcGIS Used to build Data Maps Models Applications Metadata ArcGIS Used to build Data Maps Models Applications Metadata ArcIMS Serve GIS Data Maps Apps ArcIMS Serve GIS Data Maps Apps ArcGIS Author and Manage Metadata Build Catalog ArcGIS Author and Manage Metadata Build Catalog Array of GIS Clients Access and use GIS data and services ArcReader Map Objects for Java ArcGIS Desktop & Extensions ArcPad Array of GIS Clients Access and use GIS data and services ArcReader Map Objects for Java ArcGIS Desktop & Extensions ArcPad ArcSDE Used to manage Data Metadata Transactions ArcSDE Used to manage Data Metadata Transactions ArcSDE Used to manage and distribute Metadata ArcSDE Used to manage and distribute Metadata ArcIMS Manage Metadata Provide Search Services ArcIMS Manage Metadata Provide Search Services Metadat a & Catalog Services

Market Forces Are Driving Change Organizations are moving and consolidating spatial data into relational databases to improve interoperability Organizations are moving client/server mapping applications to the web and looking to web services for the future Organizations are integrating spatial data analysis and map visualization into key business applications to improve decision making and service delivery

Views of a System Architecture ISO Reference Model of Open Distributed Processing (RM-ODP) –Enterprise Viewpoint: It is directed to the needs of the users of an information system. –Information Viewpoint: It focuses on the information content of the enterprise. –Computational Viewpoint: It deals with the logical partitioning of the distributed applications independent of any specific distributed environment on which they run. –Engineering Viewpoint: It addresses the issues of system support (platform) for distributed applications. –Technology Viewpoint: The technology model identifies possible technical artifacts for the engineering mechanisms, computational structures, information structures, and enterprise structures.

Architecture Development.

Steps Defining Architecture Requirements. –to enable the system to meet the community’s goals and objectives. Defining a Candidate Architectures. –to evolve an architecture gradually. Defining Enterprise Architecture. –integrate it into an enterprise architecture model. Defining Reference Architecture. –a working example designed and proven for use in by the participants Validating a Reference Architecture.