Information technology — SEDRIS —
Part 1:  Functional specification

0 Introduction

0.1 Purpose

SEDRIS (ISO/IEC 18023) is a technology that can be used to represent and interchange environmental data. This part of ISO/IEC 18023 defines the semantics and structure used to represent environmental data along with the means to produce and access that data. A transmittal is the realization of an environment using the SEDRIS data representation model (DRM) that can be produced and accessed through the SEDRIS application program interface (API) specified in this part of ISO/IEC 18023. A unified view of environmental data accelerates the development of applications based on such data and allows different applications to interchange environmental information. Environments may be natural, man-made, or virtual and incorporate a wide range of types of objects including celestial bodies, rivers, forests, ocean characteristics, atmospheric characteristics, avatars, ships, roads, space stations, buildings and animals. The characteristics of such objects need to be described and the relationships among them specified. This International Standard was developed to address these needs.

ISO/IEC 18023 in its entirety specifies a data representation model, an abstract transmittal format, a binary encoding, and an application program interface. Together, these components support creating and accessing transmittals as a data interchange mechanism for representing environments. Two additional International Standards, ISO/IEC 18025 — Environmental data coding specification (EDCS) and ISO/IEC 18026 — Spatial reference model (SRM), are required to completely and unambiguously describe environmental data.

The SEDRIS interchange mechanism uses the DRM, in conjunction with the EDCS and the SRM, to provide a means for defining all of the data elements and their relationships necessary to describe environmental data. These components form the central core of successful environmental data interchange and allow the unambiguous description of environmental data. The DRM can be expanded to incorporate future environmental representation needs.

The SEDRIS API is the component of the interchange mechanism that provides the means to describe and access data in a transmittal. It enables the interchange of environmental data between different proprietary database systems or formats. The API allows the underlying implementation of the transmittal to be transparent to users.

0.2 Characteristics of SEDRIS technology

Complete and unambiguous data representation

SEDRIS specifies a standard approach to describe and communicate environmental information. This approach to representation of environmental data includes support for all domains of the environment, including ocean, terrain, atmosphere and space.  In addition, SEDRIS supports the various techniques that are used to model environmental data in a variety of information technology applications.  Since such potentially diverse models and representations can describe the same object, or concept, through different data models, SEDRIS also includes the means to capture the polymorphic relationships of these representations.  Furthermore, the DRM includes the necessary data elements, and their relationship to one another, that are needed to describe the environment fully and seamlessly across all domains.

Universal, lossless data interchange

By providing a complete and unambiguous data representation and a robust interchange mechanism, standardized access and the polymorphic representation of data through the DRM ensure that users can share a common description of the environmental data. The standard access interface, and the polymorphic representation of data through the DRM, ensure that users can share a common description of the environmental data.

Standardized software interface

The SEDRIS API provides a consistent interface between a software application designed to process the environmental data and the underlying transmittal. The API decouples all SEDRIS data-consuming or data-producing applications from the transmittal’s data structures, allowing the format, its data structures and the application to evolve independently of each other.
The SEDRIS API supports many ways of accessing and manipulating transmittals. The contents of a transmittal may be traversed object by object or searched based on data attributes and spatial coverage. Access to data in transmittals is designed to be context-sensitive to support representational polymorphism. Search filters allow limiting the number of objects that are examined.
The SEDRIS API provides the means to efficiently interact with complex data types, such as data tables or images.