IndoorGML is an OGC Standard. Copyright (c) 2014,2015,2016,2018 Open Geospatial Consortium. To obtain additional rights of use, visit http://www.opengeospatial.org/legal/. The overall structure of the Multilayered Space Model constitutes a multilayered graph, where all the nodes from all n layers are included but are separated into n partitions which are connected by the inter-space connections. Furthermore the graph also contains the state transition edges (intra-space connections) Denotin the interspace connections between the SpaceLayer <SpaceLayer>s represent various space concepts such as topography, sensor, security, etc. A SpaceLayer aggregates <State> and <Transition> which are directly associated with the corresponding geometry classes. Within the dual graph structure of one layer a node in dual space represents a space (e.g. a room within a building) in primal space Within the dual graph structure of one layer, an edge in dual space represents the adjacencies or connections (e.g. doors or passages as intra-space connections) Within the dual graph structure of one layer a node in dual space represents a space (e.g. a room within a building) in primal space Within the dual graph structure of one layer a edge in dual space represents a spaceboundary (e.g. a wall between adjacenced rooms in a building) in primal space