URN Namespace for the Defence Geospatial Information Working Group (DGIWG)
RFC 6288

Internet Engineering Task Force (IETF) C. Reed
Request for Comments: 6288 OGC
Category: Informational August 2011
ISSN: 2070-1721
 URN Namespace for the
 Defence Geospatial Information Working Group (DGIWG)
Abstract
 This document describes the Namespace Identifier (NID) for Uniform
 Resource Name (URN) Namespace resources published by the Defence
 Geospatial Information Working Group (DGIWG). The DGIWG defines and
 manages resources that utilize this URN name model.
 Management activities for these and other resource types are provided
 by the DGIWG Registry System (DRS).
Status of This Memo
 This document is not an Internet Standards Track specification; it is
 published for informational purposes.
 This document is a product of the Internet Engineering Task Force
 (IETF). It represents the consensus of the IETF community. It has
 received public review and has been approved for publication by the
 Internet Engineering Steering Group (IESG). Not all documents
 approved by the IESG are a candidate for any level of Internet
 Standard; see Section 2 of RFC 5741.
 Information about the current status of this document, any errata,
 and how to provide feedback on it may be obtained at
 http://www.rfc-editor.org/info/rfc6288.
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RFC 6288 URN DGIWG Namespace August 2011
Copyright Notice
 Copyright (c) 2011 IETF Trust and the persons identified as the
 document authors. All rights reserved.
 This document is subject to BCP 78 and the IETF Trust's Legal
 Provisions Relating to IETF Documents
 (http://trustee.ietf.org/license-info) in effect on the date of
 publication of this document. Please review these documents
 carefully, as they describe your rights and restrictions with respect
 to this document. Code Components extracted from this document must
 include Simplified BSD License text as described in Section 4.e of
 the Trust Legal Provisions and are provided without warranty as
 described in the Simplified BSD License.
Table of Contents
 1. Introduction ....................................................2
 2. URN Specification for "dgiwg" NID ...............................3
 3. Examples ........................................................6
 4. Namespace Considerations ........................................6
 5. Community Considerations ........................................7
 6. Security Considerations .........................................7
 7. IANA Considerations .............................................8
 8. References ......................................................8
 8.1. Normative References .......................................8
 8.2. Informative References .....................................8
1. Introduction
 The DGIWG is a multi-national body responsible to the Defence
 organizations of member nations for coordinated advice and policy
 recommendations on standards and practices for geospatial information
 and support services. The DGIWG creates standards and recommended
 practices required to enable the provision, exchange, and
 exploitation of geospatial information. It supports the requirements
 of the North Atlantic Treaty Organization (NATO) and the other
 alliances that its member nations participate in, including
 peacekeeping sanctioned by the United Nations.
 The DGIWG has defined, and continues to define, standards, processes,
 and procedures for the use of international standards in the DGIWG
 community.
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RFC 6288 URN DGIWG Namespace August 2011
 The DGIWG geospatial standards are built upon the generic and
 abstract standards for geographic information defined by the
 International Organization for Standardization (ISO) TC/211 technical
 committee. The DGIWG makes use of the service specifications
 endorsed by the Open Geospatial Consortium (OGC).
 The DGIWG defines information components for use in the development
 of product specifications and application schemas for military
 geospatial data. The DGIWG also establishes service specifications,
 encoding formats, and testing methodologies to meet military
 geospatial intelligence requirements.
 Some of the solutions being developed by the DGIWG need XML
 namespaces that are managed so that they are unique and persistent.
 To assure that the uniqueness is absolute, the registration of a
 specific Namespace ID (NID) for use by the DGIWG was deemed
 appropriate. Therefore, a full and complete registration will follow
 the namespace specification process as defined in [RFC3406]. For the
 processes that the DGIWG uses to manage this and other registries,
 see the "DGIWG Terminology Register Technical Specification" document
 [STD-DP-07-024-ed1.0.1].
2. URN Specification for "dgiwg" NID
 Namespace ID: dgiwg
 Registration Information:
 registration version number: 1
 registration date: August 2011
 Declared registrant of the namespace:
 Registering organization: Defence Geospatial Information Working
 Group
 Name: The Secretary (attn: Mr. Paul Burton)
 Address: Defence Geospatial Information Working Group (DGIWG)
 UK Hydrographic Office
 Admiralty Way
 TAUNTON
 Somerset TA1 2DN
 United Kingdom
 Designated contact:
 Role: The DGIWG Registry Services Administrator
 Email: dgiwg-urn-admin@dgiwg.org
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RFC 6288 URN DGIWG Namespace August 2011
 Declaration of syntactic structure:
 The Namespace Specific String (NSS) of all URNs that use the
 "dgiwg" NID will have the following structure:
 urn:dgiwg:{DGIWGresource}:{ResourceSpecificString}
 where the "DGIWGresource" is a US-ASCII string that conforms to
 the URN syntax requirements [RFC2141] and defines a specific class
 of resource type. Each resource type has a specific labeling
 scheme that is covered by "ResourceSpecificString", which also
 conforms to the naming requirements of [RFC2141]. The only
 exception is that the character ":" shall not be used as part of
 the "DGIWGresource" string. This is to avoid possible confusion.
 Further, "DGIWGresource" is case sensitive.
 The DGIWG maintains a naming authority, the DGIWG Registration
 System (DRS), that will manage the assignment of "DGIWGresources"
 and the specific registration values assigned for each resource
 class. Other DGIWG standards documents will define the
 "ResourceSpecificStrings" for a given "DGIWGresource".
 Relevant ancillary documentation:
 The DGIWG defines a number of specific lists of information
 elements that can be combined with the models in product
 specifications and application schema. These are maintained by
 the DGIWG. More information about the DRS, and the registration
 activities and procedures to be followed, can be found in the
 document "DGIWG Terminology Register Technical Specification"
 [STD-DP-07-024-ed1.0.1], which provides the procedures for the
 DGIWG registration of geographical items.
 https://portal.dgiwg.org/files/?artifact_id=5438&format=doc. This
 is a stable URI. Additional information may be found at
 http://www.dgiwg.org/dgiwg/htm/registers/registers.htm.
 Identifier uniqueness considerations:
 The DRS will manage resources using the "dgiwg" NID and will be
 the authority for managing the resource type identifiers and
 subsequent strings associated with them. In the associated
 procedures, the DRS will ensure the uniqueness of the strings or
 shall permit secondary responsibility for management of well-
 defined sub-trees. URNs issued by the DRS may not be reassigned.
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RFC 6288 URN DGIWG Namespace August 2011
 The DGIWG may permit use of experimental type values that will not
 be registered. As a consequence, multiple users may end up using
 the same value for separate uses. As experimental usage is only
 intended for testing purposes, this should not be a real issue.
 Identifier persistence considerations:
 The DRS will provide clear documentation of the registered uses of
 the "dgiwg" NID. The DRS will establish a registry for
 DGIWGresources. Each DGIWGresource will have a separate
 description in the registry and may have its own sub-registry.
 The registries and information will be published and maintained by
 the DRS on its web site.
 Process of identifier assignment:
 As defined in the DGIWG Terminology Register Technical
 Specification, the DRS will provide procedures for registration of
 each type of resource that it maintains. Each such resource may
 have three types of registration activities:
 1. Registered values associated with DGIWG specifications or
 services
 2. Registration of values or sub-registries to other entities
 3. Name models to be used for experimental purposes
 Process for identifier resolution:
 The namespace is not listed with a Resolution Discovery System
 (RDS); this is not relevant.
 Rules for Lexical Equivalence:
 No special considerations; the rules for lexical equivalence of
 [RFC2141] apply.
 Conformance with URN Syntax:
 No special considerations.
 Validation mechanism:
 None specified. URN assignment will be handled by procedures
 implemented in support of DRS activities.
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RFC 6288 URN DGIWG Namespace August 2011
 Scope:
 Global
3. Examples
 The following examples are representative urns that could be assigned
 by the DRS. They may not be the actual strings that would be
 assigned.
 Example 1
 DGIWGresource "crs"
 Syntax: "urn:dgiwg:crs:<crs name>"
 ResourceSpecificString: A simple string with the name of the
 coordinate reference system (CRS) defined in a sub-registry.
 Use: Defines the urn to be used for queries to a DGIWG CRS
 registry that provides URIs for the CRS.
 Example 2
 DGIWGresource "dfdd"
 Syntax: "urn:dgiwg:fad:dfdd<fad_code>:<fad_name>"
 The DGIWG maintains a feature and attribute data (FAD) registry
 that contains registers of geographic information concepts used to
 characterize aspects of real-world phenomena for different
 information communities (https://www.dgiwg.org/FAD/registers.jsp).
 urn:dgiwg:fad:dfdd:Aerodrome:aerodrome
 urn:dgiwg:fad:dfdd:Helipad:helipad
 urn:dgiwg:fad:dfdd:AerodromeMoveAreaLighting:aerodrome
 movement-area-lighting
4. Namespace Considerations
 The Defence Geospatial Information Working Group is developing a
 variety of applications and services. Some of these services require
 that supporting information (e.g., data descriptions, attributes,
 etc.) be fully specified. For proper operation, descriptions of the
 needed supporting information must exist and be available in a
 unique, reliable, and persistent manner. These dependencies provide
 the basis of need for namespaces, in one form or another.
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 As the work is ongoing and the Defence Geospatial Information Working
 Group covers many technical areas, the possibility of binding to
 various other namespace repositories has been deemed impractical.
 Each object or description, as defined by the DGIWG, could possibly
 be related to multiple different other namespaces, so further
 conflicts of association could occur. Thus, the intent is to utilize
 the Defence Geospatial Information Working Group Registration System,
 operated by the DGIWG, as the naming authority for DGIWG-defined
 objects and descriptions.
5. Community Considerations
 The objects and descriptions required for registration services
 defined by the DGIWG are publicly available for use by other
 organizations. The DGIWG will provide public access and support for
 name requests by other organizations. This support can be enabled in
 a timely and responsive fashion as new objects and descriptions are
 produced. These will be enabled in a fashion similar to current IANA
 processes. A description of the DGIWG collaboration process is
 available on the DGIWG website: http://www.dgiwg.org/dgiwg/.
 Due to DGIWG coordination with other standards organizations and the
 use of standards from other standards organizations, there is a need
 to avoid duplicate or replicated names, such as those for coordinate
 reference systems. In order to coordinate the consistent use of
 names and namespaces, the DGIWG has formal relationships with both
 the OGC and with ISO. As long as having consistent names and
 namespaces across these organizations does have security implications
 for certain classes of applications (see below), then shared names
 and namespaces will be used.
6. Security Considerations
 For many applications that use DGIWG standards and terminology, there
 are no additional security considerations other than those normally
 associated with the use and resolution of URNs in general (which are
 described in [RFC1737], [RFC2141], and [RFC3406]). However, for a
 certain class of applications related to war fighter and peacekeeping
 operations, there is a high level of importance for having secure
 methods to access locations once the URN resolution has taken place
 (i.e., after the name-to-location resolution). In these cases,
 agreed-upon military command and control (C2) security, including
 authentication and authorization, shall be considered. However, the
 majority of communications in a military environment, just as in any
 environment, are low-level un-secure or minimally secure information.
 The Internet is well used, and a URN is necessary for compatible web
 services.
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RFC 6288 URN DGIWG Namespace August 2011
7. IANA Considerations
 This document registers with IANA a new formal URN Namespace ID,
 "dgiwg", following the procedures as defined in RFC 3406 [RFC3406].
 The completed registration template is in Section 2 of this document.
 The "Uniform Resource Names (URN) Namespaces" registry is available
 from the IANA website: http://www.iana.org.
8. References
8.1. Normative References
 [RFC2141] Moats, R., "URN Syntax", RFC 2141, May 1997.
 [RFC3406] Daigle, L., van Gulik, D., Iannella, R., and P.
 Faltstrom, "Uniform Resource Names (URN) Namespace
 Definition Mechanisms", BCP 66, RFC 3406, October 2002.
8.2. Informative References
 [RFC1737] Sollins, K. and L. Masinter, "Functional Requirements for
 Uniform Resource Names", RFC 1737, December 1994.
 [STD-DP-07-024-ed1.0.1]
 DGIWG Terminology Register Technical Specification,
 June 2008.
Author's Address
 Carl Reed, PhD
 OGC, Inc.
 2536 West Prospect
 Fort Collins, CO
 US
 EMail: creed@opengeospatial.org
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