This document defines specific National System for Geospatial-Intelligence (NSG) and Defence Geospatial Information Working Group (DGIWG) requirements, recommendations and guidelines for implementation of the International Organization for Standardization (ISO) / Open Geospatial Consortium (OGC) Web Map Service (WMS) standard which are based on ISO 19128:2005 Web Map Server Interface / OpenGIS Web Map Server Implementation Specification 1.3.0.  This document shall be referred to as the National Geospatial-Intelligence (NSG) OGC Web Map Service 1.3 Interoperability Standard, version 2.0, 20 November 2015. - View it on GitHub