OGC Glossary

Glossary of Terms - L

Local Area Network. A system for connecting computers so they can communicate with one another.
A particular system of US satellites that scan the earth at a variety of wavelengths. The satellites return information that can be used to inventory and analyze a variety of natural and human resources.
language independent
Describes a standard or specification which is not specified in terms of a specific programming language, but is implementable in a variety of languages.
layered map visualization
Pictoral representation of geographic data
Source: PreANVIL Glossary http://www.anvil.eu.com/find/Glossary-english.htm
See Location Based Services
legacy system
In computing terms, a legacy System includes software or database components inherited from a previous computing model which do not fit into an open system environment without some modification. In the case of the OpenGIS Specification, legacy systems are modified to include OpenGIS-conformant interfaces.
line string
A set of coordinate points and the lines that join them.
Location Based Services (LBS)
Source: PreANVIL Glossary http://www.anvil.eu.com/find/Glossary-english.htm
Location Based Services (or "Location Services") deliver information about location to people who are using wireless, position-aware devices such as cell phones and PDAs. A wireless-IP service that uses geographic information to serve a mobile user. Any application service that exploits the position of a mobile terminal.
Location Dependent Services
Source: PreANVIL Glossary http://www.anvil.eu.com/find/Glossary-english.htm
"Services in which the location of the client, server or both form an integral part of the service "
Location Organizer Folder (LOF)
The general, multi-source information container model for handling sets of inter-related spatiotemporal information, including images, maps, features, cables, and any other information elements (e.g., audio, video, etc).
location service
Source: PreANVIL Glossary http://www.anvil.eu.com/find/Glossary-english.htm
A service that provides the location of a moving or fixed device
Long-Term Technical Baseline Target
The Long-Term Technical Baseline Target is the subset of the elements of the Technical Plan that are scheduled to be completed greater than two calendar years into the future.
loosely-coupled service
A service that can be used to operate on multiple, unspecified datasets. Calling application has no structural dependency on the interface of called application. Call is not made in same technology as the interface of the called application.
Lempel-Zif-Welch: a popular data compression technique developed in 1977 by J. Ziv and A Lempel. Unisys researcher Terry Welch later created an enhanced version of these methods, and Unisys holds a patent on the algorithm. It is widely used in many hardware and software products, including V.42bis modems, GIF and TIFF files and PostScript Level 2.

Glossary of Terms - M

A two-dimensional visual portrayal of geospatial data. A map is not the data itself.
map projection
A coordinate conversion from a geodetic coordinate system to a planar surface, converting geodetic latitude and longitude to plane (map) coordinates. The result is a two-dimensional coordinate system called a projected coordinate reference system.
map scale
The relationship between distance on a map and the corresponding distance on the earth`s surface. Map scale is often recorded as a representative fraction such as 1:1,000,000 (1 unit on the map represents a million units on the earth`s surface) or 1:24,000 (1 unit on the map represents 24,000 units on the earth`s surface). The terms `large` and `small` refer to the relative magnitude of the representative fraction. Since 1/1,000,000 is a smaller fraction than 1/24,000, the former is said to be a smaller scale. Small scales are often used to map large areas because each map unit covers a larger earth distance. Large-scale maps are employed for detailed maps of smaller areas.
An observation event whose value property is a value of some natural phenomenon. A measurement usually refers to the measuring device and procedure used to determine the value, such as a sensor or observer, analytical procedure, simulation or other numerical process. A measurement feature binds the result to the (spatiotemporal) location where the measurement was made.
message broker
Hubs designed to route and manage message traffic between various applications. May include transformation for incompatible messages.
Source: ISO 19115; KOGIS Switzerland; Co-ordination for GIS in the federal administration of Switzerland
"Data about data or a service. Metadata is the documentation of data. In human-readable form, it has primarily been used as information to enable the manager or user to understand, compare and interchange the content of the described data set. In the Web Services context, XML-encoded (machine-readable and human-readable) metadata stored in catalogs and registries enables services to use those catalogs and registries to find data and services.
metadata dataset
Source: ISO 19101
Metadata describing a specific dataset
metadata entity
Source: ISO 19115
Group of metadata elements and other metadata entities describing the same aspect of data. Note 1: A metadata entity may contain one or more metadata entities. Note 2: A metadata entity is equivalent to a class in UML terminology
metadata schema
Source: ISO 19101
Coceptual schema describing metadata Note: ISO 19115 describes a standard for metadata schema.
metadata section
Source: ISO 19115
Subset of metadata that defines a collection of related metadata entities and elements.
metadata translator
Software based on the OpenGIS Specification that will be configured by two diverse Information Communities to enable automated data integration or sharing to the degree that their metadata schema overlap.
Mid-Term Technical Baseline Target
The Mid-Term Technical Baseline Target is the subset of the elements of the Technical Plan that are scheduled to be completed between one and two calendar years into the future.
Software in a distributed computing environment that mediates between clients and servers.
OGC`s Multi-Hazard Mapping Initiative (MMI) Phase I (2001) was a pilot project sponsored by the US Federal Emergency Management Agency (FEMA) that established a limited operational framework of interoperable services to illustrate the advantages of using products with OGC interfaces to access, fuse and visualize critical spatial information in support of FEMA multi-hazard mitigation, response and recovery functions.
modeling languages
Well-known "languages" to encode the semantics, syntax and schema of geospatial and geoprocessing-related information resources. They apply to all Application Domain Models and Runtime (Model) Components.
OGC`s Military Pilot Project (MPP) (2001) was a collaborative effort that tested the interoperability of commercial geoprocessing products in the defense and intelligence (DI) domain.

Glossary of Terms - N

National Mapping Agencies
National government agencies, such as the UK's Ordnance Survey, France`s Institut Geographique National (IGN) and the US's US Geological Survey and Federal Geographic Data Committee, that are chartered to provide national mapping products and services.
National Spatial Data Infrastructure (NSDI)
Information Infrastructure elements that make digital geographic information a part of everyone's digital information environment: data content and metadata standards; national Framework (base) data; metadata to help inventory, advertise, and intelligently search geographic data sets; a clearinghouse that allows for catalog searches across multiple geodata servers on the Internet; commercial geoprocessing products that interoperate through interfaces that conform to interoperability interface specifications; and partnerships to advance data sharing and NSDI development.
navigation service
An enhanced version of the Route Service, which is a network-accessible service that determines travel routes and navigation information between two or more points.
Non-governmental organization
National Information Infrastructure. A nation`s entire collection of public and private digital information, physical networks and network software, computers, and knowledge about how to use them.
National Mapping Agency
0-dimensional topology primitive (see OGC Abstract Specification (Topic 1) clause 7.3.12)
Neutral Transfer Format. Interchange of geographic information within UK

Glossary of Terms - O

Data and processing functions packaged into a small, discrete, interoperable module. Also, in a specific OGC context, an XML document element of a type derived from AbstractGMLType
Object Oriented (OO)
Software in which data and processing functions are packaged into small, discrete, interoperable modules, offering advantages such as portability and easy maintainability.
object technology
Software scheme in which data and processing functions are packaged into small, discrete, interoperable modules, offering advantages such as portability and easy maintainability.
observation domain model
The definition of a specific observation type in accordance with the general observation model.
Observation Model
The general model for representing observations of earth phenomena; general observation model for describing well-known observations.
Source: PreANVIL Glossary http://www.anvil.eu.com/find/Glossary-english.htm
Open GIS Consortium, Inc. http://www.opengis.org
OGC Interoperability Program
The OGC Interoperability Program provides an industry consensus process to develop, test, demonstrate, and promote the use of standard interfaces and protocols that enable interoperable geoprocessing. The Interoperability Program organizes and manages Interoperability Initiatives, including Testbeds, Pilot Projects, Planning Studies, Insertion Projects, and Feasibility Studies. Technical documents, training materials, test suites, reference implementations and other resources developed in these initiatives become available for use by members and the public on the OGCNetwork.
OGC Network
An OGC web site (http://www.ogcnetwork.org/ ) that provides a Directory of OGC services, fora, mail lists, specifications, discussion papers, Collaborative Test Environment services, and other OGC-related resources.
OGC Specification Program
In the OGC Specification Program, the OGC Technical Committee reviews specifications for interfaces and encodings developed either in the Interoperability Program by groups of members, or through an internal proposals process. The Technical Committee and Planning Committee then approve these as OpenGIS® Specifications for release to the public.
OGC Technical Baseline
See Technical Baseline.
OGC Technical Committee
The OGC Technical Committee is the primary operational unit of the OpenGIS specification development and adoption process. It is comprised of the technical representatives of all OGC member organizations and is charged with creating OpenGIS Specifications and maintaining the OGC Abstract Specification. The Technical Committee does the bulk of its work through its Working Groups (WGs).
Source: PreANVIL Glossary http://www.anvil.eu.com/find/Glossary-english.htm
Open GIS Consortium (Europe) Limited: a business supporting OGC in Europe. http://www.opengis.co.uk
Object Linking and Embedding/Common Object Model. A DCP developed by Microsoft.
A state (referring to equipment such as computers, plotters, printers, and digitizers) of being turned on and actively communicating with a computer or computer network.
open interface
An interface that implements a standard specification developed in an open consensus process. (See interface.)
Open Location Services
Open Location Services (OpenLS) is a multi-phase project which is focused on defining and building the "core" Location Based Services (LBS) standards and information framework for LBS application services in close coordination with other related industry standards groups.
open platform
In the past, the term platform denoted any specific hardware and operating system combination, such as the Windows/Intel platform. It now used more generally describes an application programming interface (API) or set of APIs that provide access to computing power, database, GIS or other services hidden "underneath" those APIs. The acronym "API" is generally giving way to "interface" in programmer-speak. No single vendor provides an open platform unless all the exposed interfaces are open interfaces as defined above. An open platform needs to be like the IT industry`s Web Services platform, which is still, as of August, 2003, largely unencumbered by proprietary restrictions and is the product of a non-exclusive consensus process.
open source
It is important not to confuse "open source" with "open standards." They are entirely different. The special licenses that govern use and sale of such software exist not to ensure profits to the software`s owner, but to ensure that the software`s source code remains in the public domain (free to all), though companies are allowed to sell products that include some or all of the source code. Open source software is usually developed not by single company but by a distributed team of developers, typically an informal ad hoc group of volunteers.
open specification
A specification that promotes interoperability through its public availability to developers, who use it to develop software or hardware compatible with the common resource described in the specification. Open specifications are generally consistent with related standards and are updated to conform with new standards and new technologies. They may be developed and maintained, as in the case of OpenGIS Specifications, by a public open consensus process.
open standards
An "open standard" is one that: 1. Is created in an open, international, participatory industry process 2. Is freely distributed and openly accessible 3. Does not discriminate against persons or groups 5. Ensures that the specification and the license must be technology neutral: Its use must not be predicated on any proprietary technology or style of interface.
open system
Open systems are systems that interoperate through open interfaces, protocols etc. developed and maintained in an inclusive, open consensus process. Open systems promote application portability, scalability, interoperability, diversity, manageability, extensibility, compatibility with legacy components, and user portability.
open system environment
A computer environment specified by a set of standards and profiles for interfaces, services, and formats for an open system.
OpenGIS Abstract Specification
A document that captures the OGC member consensus on a computing technology independent specification for interfaces, protocols or schemas for interoperable geoprocessing. The Abstract Specification is that part of the OpenGIS Specification created by the OGC Technical Committee to provide a high level description of the functionality to be provided in OpenGIS Implementation Specifications.
OpenGIS Implementation Specification
A document containing a computing platform dependent specification for application program interfaces, protocols etc. OpenGIS Implementation Specifications contain detailed software specifications for implementing standard interfaces, protocols etc. on particular distributed computing platforms such as the Web, SQL, OLE/COM and CORBA.
OpenGIS Reference Model (ORM)
The ORM is a document, part of the OGC Technical Baseline, that provides an overall conceptual framework for building geospatial processing into distributed systems in an incremental and interoperable manner.
OpenGIS Specification
An open software standard developed and adopted in OGC`s open consensus process that enables interoperable geoprocessing, which includes: real-time data sharing and process execution between GIS systems from different vendors; interoperation between dissimilar types of geoprocessing systems (GIS, Earth imaging, surveying and mapping, navigation, etc.); and efficient discovery of and access to remote geodata and geoprocessing resources in distributed computing environments.
OpenGIS, Open GIS and open GIS
OGC registered the trademark "Open GIS" and OpenGIS" in countries around the world to assert the importance of open standards in geoprocessing and to protect these standards with a legal brand. The phrase "open GIS" (with a small "o") is also a trademark of OGC, with the same meaning as "Open GIS," though "open GIS" is not a registered trademark.
See Open Location Services.
OpenLS Core Services
The basic services that comprise the open service platform (GeoMobility Server) defined under OpenLS.
A single step performed by a computer in the execution of a program, or, in the context of object-oriented programming: Specification of an interaction that can be requested from an object to effect behavior. ISO 19119
OpenGIS Reference Model
orthophoto map
Source: http://www.eurogeographics.org/Projects/GDDD/GDDD/lists/products.htm#52
Digital or digitized aerial photographs in which the pixels are geometrically rectified and given geographical references. The data structure is raster. An orthophoto map may include details of topography and names.
Use of photogrammetric techniques to adjust and correct distortions in mages.
OGC Web Services.
OWS Service Framework
(OSF) Identifies services, interfaces and exchange protocols that can be utilized by any application. OpenGIS Services are implementations of services that conform to OpenGIS Implementation Specifications. Compliant applications, called OpenGIS Applications, can then "plug into" the framework to join the operational environment.

Glossary of Terms - P

Portable Document Format. An Adobe file format readable with free software (Acrobat Reader)
Use of aerial photographs to produce planimetric and topographic maps of the earth`s surface and of features of the built environment. Effective photogrammetry makes use of ground control by which aerial photographs are carefully compared and registered to the locations and characteristics of features identified in ground-level surveys.
pilot project
In the context of the OGC Interoperability Program, a project to introduce new technology products into an operational environment to discover the effectiveness of these products and the new approaches they enable, and to provide feedback into the Specification Program.
Planning Committee
The OGC Planning Committee identifies market opportunities for interoperability and uses this information to document and maintain a "Technology Roadmap" that sets forth the plan, schedule and rationale for OGC activities.
planning study
In OGC: Strategic study that assesses opportunities to expand and sustain an organization's interoperability capacity.
Another term for computer hardware, including microcomputers, workstations, and mainframe computers, or for underlying software, like an operating system, that provides services to layered software.
platform independent
Depends on context, but in general, when discussing software, platform independence means the software can be run on any computer or operating system or distributed computing platform.
Portable Network Graphic. A format for Web graphics
point of interest
A location (with a fixed position) where one can find a place, product or service, typically identified by name rather than by address and characterized by type, which may be used as a reference point or a target in a location based service request, e.g., as the destination of a route.
point to grid interpolation
Source: GETIS glossary
The conversion from a geospatial data set that represents a surface with points and their attributes (e.g. terrain heights) to a grid (raster) data structure that represents the same surface. The estimation of attribute values of the surface at an unsampled point in the grid is based on the known attribute values of surrounding points in the point dataset.
Source: AGI glossary. http://www.geo.ed.ac.uk/agidict/welcome.html
A feature used to represent areas. A polygon is defined by the lines that make up its boundary and a point inside its boundary for identification. Polygons have attributes that describe the geographic feature they represent.
polygon overlay
Source: AGI glossary. http://www.geo.ed.ac.uk/agidict/welcome.html
"The process of superimposing two or more polygons, through registration to a common co-ordinate system. Such an overlay procedure determines the spatial coincidence of two sets of polygon features and creates a new set of polygons based upon overlay operating."
A Web site that provides a view into a universe of content and activity through a variety of links to other sites, communication and collaboration tools, and special features geared toward the community served by the portal.
The presentation of information to humans, e.g., a map. In the context of the Web, portrayal refers to how data is presented for the user. Map portrayal, for example, is concerned with shape and color of symbols representing features, rules for displaying text labels, rules for showing/not showing symbols based on zoom extent, etc.
Portrayal Service
Defines a standard interface for producing visual pictures from coverage data. CPS extends the WMS interface and uses the Styled Layer Descriptor (SLD) language to support rendering of WCS coverages. provide visualization of geospatial information. Portrayal Services are components that, given one or more inputs, produce rendered outputs (e.g., cartographically portrayed maps, perspective views of terrain, annotated images, views of dynamically changing features in space and time, etc.). Examples include: Map Portrayal Services (MPS), Coverage Portrayal Services (CPS) and Mobile Presentation Services.
Refers to the level of measurement and exactness of description in a GIS database. Precise locational data may measure position to a fraction of a unit. Precise attribute information may specify the characteristics of features in great detail. It is important to realize, however, that precise data - no matter how carefully measured - may be inaccurate. Surveyors may make mistakes or data may be entered into the database incorrectly. Therefore, a distinction is made between precision and accuracy.
presentation (map portrayal) service
A network-accessible service that portrays a map made up of a base map derived from any geospatial data and a set of ADT's as overlays.
process domain model
Data model that characterizes well-known, domain-specific business processes. These models capture business rules, policies, tasks, and procedures in the form of processing chains. Microsoft, IBM and others are collaborating on a standard methodology for online workflow and service chaining. When this standard stabilizes and emerges, organizations will start testing this technology and adapt it in a wide range of workflows. When that happens, many Process Domain Models will result.
processing services
OWS Services that operate on geospatial data and provide 'value-add' services for applications. They can transform, combine, or create data. Processing Services can be tightly or loosely coupled with other services, such as Data and Portrayal Services. Processing Services can be sequenced into a 'chain' of services to perform specialized processing in support of information production workflows and decision support. Examples include: Coordinate Transformation Services (CTS), Geocoder Services, Route Determination Services etc.
A collection of standards, with parameters, options, classes, or subsets, necessary for building a complete computer system, application, or function. An implementation case of a more general standard or set of standards.
A facet or attribute or an object referenced by a name.
A set of semantic and syntactic rules that determine the behavior of entities that interact.
In the context of the OGC Interoperability Program, prototyping refers to developing a new candidate standard interface, protocol, schema etc. for the purpose of learning about it and guiding future OpenGIS Specification development.
In the context of OGC Web Services, just as non-spatial Web pages "publish" their contents - make them discoverable - through HTML, metadata, geodata and geoprocessing services servers publish their contents and capabilities through XML metadata contained in feature type registries, feature instance catalogs, and service registries.
publish, find, bind
In the context of Web Services, publish means to advertise data and services to a broker (such as registry, catalog or clearinghouse). A service provider contacts the service broker to publish (or unpublish) a service. A service provider typically publishes to the broker metadata describing its capabilities and network address. Find is used by service requestors to locate specific service types or instances. Service requestors describe the kinds of services they're looking for to the broker and the broker responds by delivering results that match the request. Service requestors typically use metadata published to the broker to find service providers of interest. Bind results after a service requestor and a service provider successfully negotiate so the requestor can access and invoke services of the provider. A service requestor typically uses service metadata provided by the broker to bind to a service provider. The service requestor can either use a proxy generator to generate the code that can bind to the service, or can use the service description to manually implement the binding before accessing that service.

Glossary of Terms - R

Source: PreANVIL Glossary http://www.anvil.eu.com/find/Glossary-english.htm
The representation of spatial data as a matrix of valued cells. Originally, a raster was a scan line in an electronic display such as a television or computer monitor. In geoprocessing, raster refers to a digital representation of the extent of geographic data sets using "grid cells" in a matrix. A raster display builds an image from pixels, small square picture elements of coarse or fine resolution. A raster database maintains a "picture" of reality in which each cell records some sort of information averaged over the cell`s area. The size of the grid cell may range from centimeters to kilometers. Many satellites transmit raster images of the earth`s surface. Reflectance of sunlight at a certain wavelength is measured for each cell in an image.
Refers generally to systems that respond (almost) immediately or synchronously to external events.
Recommendation Paper
An OGC document containing discussion of some technology or specification area, prepared by a Working Group for release to the public. Recommendation Papers are the official position of the OGC and thus represent an endorsement of the content of the paper.
reference data
European term for a collaborative effort to create a widely available source of basic geographic data, providing national or European coverage of a set of common digital geographic data such as Elevation, Transportation, Hydrography, Cadastral, Geodetic Control, Governmental Units, etc. (Similar to "framework data" in the U.S.)
Reference Implementation
An operational, conformant implementation of an implementation specification, together with available source code, that is made available for public use for testing and development purposes. (a Reference Implementation refers to one or more OpenGIS Implementation Specifications.)
reference model
Provides the complete scientific and engineering contextual framework for a technology area. Includes the underlying elements, rules and behaviors.
register of geodetic points
Source: http://www.eurogeographics.org/Projects/GDDD/GDDD/lists/products.htm#52
"A catalogue of geodetic control points, e.g. trigonometric points and leveling benchmarks."
register of land
Source: http://www.eurogeographics.org/Projects/GDDD/GDDD/lists/products.htm#52
"A general term used for the designation of registers for ownership of land, e.g. cadastre and registers of territorial rights."
Registry Model
The general model for online registries. Sensor Model - The general model for sensor phenomena; the general sensor model for describing well-known sensors.
registry object
Every registered resource is a registry object. Dataset metadata and service metadata are examples of registry objects. All metadata and data types are regarded as registry objects.
registry services
OWS Services that provide a common mechanism to classify, register, describe, search, maintain and access information about resources available on a network. Resources are network addressable instances of typed data or services.
Relational Data Base
Stores data in such a way that it can be added to, and used independently of, all other data stored in the database. Users can query a relational database without knowing how the information has been organized. Although relational databases have the advantages of ease-of-use and analytical flexibility, their weakness can be slower retrieval speed. SQL (structured query language) is an interface to a relational database.
Remote Procedure Call (RPC)
An API for remote (across the network) execution of detailed functions.
remote sensing
Acquisition of raster images of the Earth, often involving spectral frequencies other than the visible band, by devices typically carried on airborne or satellite platforms. Sometimes refers also to image analysis of these images.
reporting group
Source: ISO 19113; ISO 19109
Data with common characteristics forming a subset of a dataset. Note 1: Common characteristics can include belonging to an identified feature type, feature attribute or feature relationship; sharing of data collection criteria; sharing original source; or being within a specified geographic or temporal extent. Note 2: A reporting group can be as small as a feature instance, an attribute value, or a single feature relationship.
Invocation of an operation by a client
Request for Comment (RFC)
In the context of OpenGIS Specification Development, an explicit request to the industry for comments concerning a particular technology that an OGC Technical Committee Working Group or Interoperability Initiative is considering for development or adoption as an OpenGIS Specification.
Request for Information (RFI)
In the context of OpenGIS Specification Development, a general request to the industry to submit information to one of the OGC Technical Committee Working Groups.
Request for Proposals (RFP)
In the context of OpenGIS Interoperability Program, an explicit request to the industry to submit proposals for work to be performed as part of an Interoperability Initiative.
Result of an operation returned from a server to a client
reverse geocoder service
A network-accessible service that transforms a given position into a normalized description of a feature location (Address with Point), where the address may be defined as a street address, intersection address, place name or postal code
Reference Model for Open Distributed Processing (ISO/IEC 10746). In RM-ODP, Architecture is defined as a set of components, connections, and topologies defined through a series of views: enterprise, information, computation, engineering and technology.
route service
A network-accessible service that determines travel routes and navigation information between two or more points.
Source: PreANVIL Glossary http://www.anvil.eu.com/find/Glossary-english.htm
Research and Technology Development: a term used in the European IST program.

Glossary of Terms - S

Spatial Archive and Interchange FormatÂ
The ability to change the component configuration of a system to fit desired application contexts.
scanned map
Source: http://www.eurogeographics.org/Projects/GDDD/GDDD/lists/products.htm#52
Analogue maps digitized by scanning. The data structure of scanned maps is raster.
A structured framework. A metadata schema specifies the order and types and labels of information elements describing a geodata set.
Standards based commercial off-the-shelf software. ("Off the shelf" means that the product is commercially available, without any need for customization.)
Source: PreANVIL Glossary http://www.anvil.eu.com/find/Glossary-english.htm
"(Geo)Spatial Data Infrastructure: a comprehensive package of consensus and initiatives required to enable complete provision of data, access and privacy within the territory of the designated infrastructure."
Source: PreANVIL Glossary http://www.anvil.eu.com/find/Glossary-english.htm
Standards Development Organization: any international organization that develops standards for the whole community. Includes de jure SDOs and standards consortia.
Spatial Data Transfer Standard. A standard vector format developed by the US Federal Geographic Data Committee.
semantic translator
A collection of mappings between a target Information Community`s data model and a source Information Community`s data model, generally held and maintained by the target Information Community, though both Information Communities may participate in configuring it. Usually expressed in terms of metadata, features, attributes and rules that permit information integration to occur when a feature collection is imported to the target Information Community from a source Information Community.
Sensor Collection Service (SCS)
Provides a web-enabled interface to a sensor, collection of sensors or sensor proxy. The Sensor Collection Service provides a standard interface for clients to collect and access sensor observations and manipulate them in different ways. SCS instances are collection points on the web for disparate types and instances of sensors. SCS instances deliver sensor observation values (e.g., temperature, ppm, chemical type) in response to queries form HTTP clients.
sensor domain model
The definition of a specific sensor type in accordance with the general sensor model.
Sensor Model Language
(SML) OGC`s XML-based language for describing and encoding sensors (in situ, satellite and airborne).
sensor web
A networked collection of sensors that can be remotely read and perhaps also controlled.
Sensor Web Enablement
OGC`s initiative to develop standards that support linking of environmental sensors to the World Wide Web. A Sensor Collection Service (SCS) server gathers readings from in-situ environmental sensors via a private network (cellular, microwave, etc.), and provides summaries or interpretations of those readings to SCS clients over the Web.
A computation performed by a software entity on one side of an interface in response to a request made by a software entity on the other side of the interface. A collection of operations, accessible through an interface, that allows a user to evoke a behavior of value to the user. ISO - 19119
service chain
A sequence of services where, for each adjacent pair of services, occurrence of the first action is necessary for the occurrence of the second action ISO 19119.
service interface
Source: ISO 19101
Shared boundary between an automated system or human being and another automated system or human being
service metadata
The most basic operation all OGC services must provide is the ability to describe themselves. This "Get Capabilities" operation, yielding a capabilities document, is common to all OWS1 services. An XML vocabulary comprised of several parts for describing different aspects of a service. The first unit describes the service interface in sufficient detail so that an automated process can read the description and invoke an operation that the service advertises. A second unit describes the data content of the service (or the data it operates on) in a way that enables service requestors to dynamically compose requests for service.
Service Model
The general model for online services.
service request
A request by a client of an operation from a service.
An ESRI published spatial data format.
Standard interchange format. SIF is a format which allows data to be transferred among dissimilar computer systems. SQL stands for Structured Query Language, a relational database.
Simple Feature Model
The general, descriptive model for how earth features may be represented as vector objects (i.e., points, lines and polygons).
Source: PreANVIL Glossary http://www.anvil.eu.com/find/Glossary-english.htm
Small or Medium Sized Enterprise (1-500 employed persons)
Source: http://www.softwareag.com/xml/about/glossary.htm
"Simple Object Access Protocol, a method invented by Microsoft to use RPC over the internet via HTTP calls. SOAP is now published as an W3C Note and implemented, among others, as part of the Apache XML Project." SOAP is a protocol specification that defines a uniform way of passing XML-encoded data. It also defines a way to perform remote procedure calls (RPCs) using HTTP as the underlying communication protocol. Development of SOAP is in the care of the W3C`s XML Protocols Working Group.
spatial reference system
Source: The OpenGIS® Abstract Specification Topic 2: "Spatial Referencing by Coordinates" http://www.opengis.org/techno/abstract/02-102.pdf
As defined in the OpenGIS Abstract Specification Topic 2 and ISO 19111. Position on or near the Earth's surface can be described by spatial reference systems. These are of two basic types: those using coordinates; and those based on geographic identifiers (for example postal addresses, administrative areas). Spatial referencing by geographic identifiers is defined in ISO 19112, Geographic information - "Spatial referencing by geographic identifiers." The subject matter of The OpenGIS® Abstract Specification Topic 2: "Spatial Referencing by Coordinates" is spatial referencing by coordinates.
Spatial Web
The Spatial Web is the spatially enabled World Wide Web. It is also the set of Web-resident open geospatial resources -- data, schemas and services - that enable people to publish, find and use Web-resident geospatial information off all kinds.
A document written by a consortium, vendor, or user that specifies a technological area with a well-defined scope, primarily for use by developers as a guide to implementation. A specification is not necessarily a formal standard.
Specification Program
The OGC Specification Program provides an industry consensus process to plan, review and officially adopt OpenGIS Specifications for interfaces and protocols that enable interoperable geoprocessing services, data, and applications. The OGC bodies involved in the Specification Program are the Technical Committee, Planning Committee, and Strategic Member Advisory Committee.
Source: http://www.softwareag.com/xml/about/glossary.htm
Structured Query Language. "SQL is a standard interactive and programming language for getting information from and updating a database. Although SQL is both an ANSI and an ISO standard, many database products support SQL with proprietary extensions to the standard language"
A document that specifies a technological area with a well-defined scope, usually by a formal standardization body and process.
State Plane Coordinate System (SPC)
A locational reference system developed in the U.S. in the 1930s which provides positional descriptions accurate to 1 foot in 10,000. The SPC system divides the United States into 125 zones (5 cover Texas) and employs both Lambert conformal and Transverse Mercator projections (depending upon a state`s size and shape). Within any given SPC zone, X-Y coordinates are given in eastings and northings. A central meridian passes each zone and is given a false easting of 2 million feet. A false northing of 0 feet is established below the southern limit of each zone.
stove pipe or stove piped
Colloquial term describing systems that are 'islands of automation,' that do not interoperate with other systems. Data in at the bottom, data out at the top, no sharing of data or services laterally.
Strategic Member Advisory Committee (SMAC)
The SMAC is granted authority to operate by the OGC by-laws. The SMAC has as a primary responsibility to recommend areas of strategic opportunity for Consortium operations and to recommend resource strategies in support of Consortium programs to the Board of Directors, Consortium staff and the Membership.
structured code
Refers to software designed such that a small central program makes calls to subroutines organized in external libraries: as opposed to the `spaghetti` code of large monolithic programs with integral functions and subroutines. This approach enables libraries called application programming interfaces (APIs) to provide a standard set of `hooks` by which a program can cooperate with other programs.
Styles provide the mapping from feature types and feature properties and constraints to parameterized symbols used in drawing maps
Styled Layer Descriptors (SLD)
A map-styling language for producing georeferenced maps with user-defined styling
Source: http://www.softwareag.com/xml/about/glossary.htm
"A program written in a stylesheet language for converting and/or presenting HTML, SGML, or XML documents. Stylesheet languages are e.g. CSS for HTML (and CSS2 for XML too), XSL for XML and FOSI and DSSSL for both SGML and XML."
Collection of components. E.g. Customer Management contains many software components including Party, Location, Post Code look-up, and assign new ID number.
2-deminsional geometric primitive, locally representing a continuous image of a region of a plane. (see OGC Abstract Specification (Topic 1) clause 6.3.17)
Surface Configuration Model
Defines the geometric characteristics of the Earth`s surface, exclusive of features which fall upon the surface; defined in terms of elevation, shape, roughness, slope, and aspect, with the later properties possibly derived from elevation.
"Scalable Vector Graphics, a language for describing two-dimensional vector and mixed vector/raster graphics in XML. SVG graphic types include text and XSLT can transform XML documents into SVG output. Thus SVG is a possible replacement for XSL FO. SVG tools are provided by IBM, CSIRO and Adobe." SVG is a standard application programming interface (API) for displaying graphics encoded in XML. SVG is used for presentation of GML data.
Symbols are bundles of predefined graphical parameters and predefined fixed graphic "images".
Methodology for describing symbols and mapping of the schema to an application schema. Portrayal requires symbology.
Calling application requires response to request before proceeding.
System Internal Interface (SII)
An interface between components within an application platform.

Glossary of Terms - T

Source: PreANVIL Glossary http://www.anvil.eu.com/find/Glossary-english.htm
Technical Committee within ISO for Geographic Information/ Geomatics standards
Technical Baseline
The OGC Technical Baseline, at any point in time, is the set of all Adopted Specifications plus all other technical documents that have been approved by the OGC Technical and Planning Committees, including the OpenGIS Reference Model, OpenGIS Abstract Specifications, Recommendation Papers, and Discussion Papers.
Technical Committee
In the OGC Specification Program, the OGC Technical Committee reviews specifications for interfaces and encodings developed either in the Interoperability Program by groups of members, or through an internal proposals process. The Technical Committee and Planning Committee then approve these as "adopted" OpenGIS® Specifications for release to the public. The OGC Technical Committee is comprised of the technical representatives of all OGC member organizations. The Technical Committee does the bulk of its work through its Working Groups.
Technical Plan
The OGC Technical Plan, at any point in time, is the set of planned modifications and additions to the Technical Baseline that could occur over a given time horizon. This includes both the specification documents as well as the Supporting Material.
Technology Insertion Project
In OGC: Collaborative project focusing on expanding an organization's interoperability capacity by laying the infrastructure (groundwork) for open implementations.
technology viewpoint
RM-ODP viewpoint concerned with the underlying infrastructure in a distributed system. It describes the hardware and software components used in a distributed system. The infrastructure, which may be provided by a Distributed Computing Platform (DCP), allows objects to interoperate across computer networks, hardware platforms, operating systems and programming languages.
temporal reference system
The temporal reference system package in the ORM provides elements for describing temporal reference systems, e.g., calendars and clocks.
In the context of OGC's Interoperability Program, a testbed is a collaborative activity in which sponsors provide interoperability requirements and financial support and technology providers team to develop prototype interoperability interfaces, protocols etc. that meet those requirements. The testbed concludes with a public demonstration, and the prototype-derived specifications are submitted to the OGC Technical Committee for review and approval.
thematic map
A map showing, by color or pattern, the distribution of a single phenomenon
thick clients
Clients that handle much of the necessary computation and data/metadata management themselves; and rather than invoking the processing services of other components, they obtain their inputs through low-level data-access requests.
thin clients
Clients that rely on invoking the services of other components (servers, middleware) for most of the computation they need to function in the system; they also rely on other components to manage most of the data and metadata they use.
Tagged Image File Format. A graphic file format developed by Aldus and Microsoft.
Topologically integrated geographic encoding and referencing file. This is a type of digital map developed by the U.S. Bureau of the Census to support the 1990 population census. Census maps in TIGER format succeed the previous DIME format. TIGER files are available for every county in the United States and for the millions of census blocks in urban areas. Although the accuracy of TIGER files varies from county to county, partly for reasons beyond the control of the Bureau, they are likely to improve in coming decades. The TIGER files are a particularly important resource for many urban GIS. The Census Bureau is moving to provide TIGER data in GML.
tightly coupled data and service
An instance of a service associated with a specific instance of a dataset.
Calling application must have detailed knowledge of interfaces of called application. Call is likely made in same technology, and using same call structure.
A software component, sometimes called an application object, which can act as either a service provider or service requester within an application platform.
topographic map
Source: AGI glossary. http://www.geo.ed.ac.uk/agidict/welcome.html
"A map whose principal purpose is to portray the features of the earth`s surface. These features might include the cultural landscape, but normally refer to the terrain and its relief."
Properties of geometric forms that remain invariant when the forms are deformed or transformed by bending, stretching, and shrinking. Among the topological properties of concern in GIS are connectivity, order, and neighborhood. One productive use of topology is to accelerate computational geometry. Geometric calculations such as containment (point-in-polygon), adjacency, boundary, and network tracking are computationally intensive. For this reason, combinatorial structures known as topological complexes are constructed to convert computational geometry algorithms into combinatorial algorithms. Another purpose is, within the geographic information domain, to relate feature instances independently of their geometry.
A kind of intermediary service which acquires services from one or more providers for `resale` to a service requester. The trader service insulates requester and provider services from having to interact directly with one another. The trader is responsible to the requester for all aspects of the requested service.
transfer protocol
Source: ISO 19118
Common set of rules for defining interactions between distributed systems.
The process of converting data or commands from one computer format to another, or from one computer language to another.
The ability of systems or components of systems to hide the details of their implementations from other client or server systems or components of systems.
An ordered set. Such a set of coordinates that define a point.