2 Terms and definitions
For the purposes of this document, the following terms and definitions apply. •
Message
•
Action
•
Interface: a named set of operations that characterize the behavior of an entity.
•
Service: a distinct part of the functionality that is provided by an entity through messages different from current OGC definition
•
Client: a software component that can invoke an action from a server.
•
Request: an invocation by a client of an operation.
•
Response: the result of an operation returned from a server to a client. 3 Conventions
3.1 Normative verbs
In the sections labeled as normative, the key words must, must not, required, shall, shall not, should, should not, recommended, may, and optional in
this document are to be interpreted as described in Internet RFC 2119 [1].
3.2 Abbreviated terms
CGI Common Gateway Interface
DCP Distributed Computing Platform
DTD Document Type Definition
EPSG European Petroleum Survey Group
GIS Geographic Information System
GML Geography Markup Language
HTTP Hypertext Transfer Protocol
IA Image Archive
IETF Internet Engineering Task Force
MIME Multipurpose Internet Mail Extensions
OGC Open GIS Consortium
2
© OGC 2003 – All rights reserved
OMF OpenGIS® Messaging Framework
OWS OpenGIS® Web Service
SOAP Simple Object Access Protocol
URL Uniform Resource Locator
WCS Web Coverage Service
WFS Web Feature Service
WOS Web Object Service
XML Extensible Markup Language
3.3 Use of examples
This specification makes extensive use of XML examples. They are meant to illustrate the various aspects of the OMF discussed in this specification. While every effort has
been made to ensure that the examples are well formed and valid in many cases this goal was sacrificed for the sake of clarity. For example, many examples are formatted in a
specific way to highlight a particular aspect that would render the example invalid from the perspective of an XML validation tool. Further, most examples reference fictitious
servers and data.
Thus, this specification does not assert that any XML encoded example, copied from this document, will necessarily execute correctly or validate using a particular XML
validation tool.
4 Messaging-style versus RPC-style communication
There are two styles of communication between processes that are possible: Remote Procedure Call RPC style and message-style. This section attempts to discuss about
the pros and cons of both approaches and explains why the messaging style is more appropriate for the OpenGIS web service architecture.
4.1 Overview of RPC style
