The Device Topologyreflects the communication topology of the Devices. It includes Devicesand the Networks. The entry point DeviceTopologyis the starting point within the AddressSpaceand is used to organize the communication Devicesfor the top level Networksthat provide access to all instances that constitute the Device Topology((sub-)networks, devices and communication elements).

The DeviceTopologynode is formally defined in Table 42.

Table 42– DeviceTopology definition

Attribute	Value
BrowseName	DeviceTopology
References	NodeClass	BrowseName	DataType	TypeDefinition
OrganizedBy by the Objects Folder defined in OPC 10000-5
HasTypeDefinition	ObjectType	BaseObjectType	Defined in OPC 10000-5.
HasProperty	Variable	OnlineAccess	Boolean	PropertyType
Conformance Units
DI DeviceTopology

OnlineAccessprovides a hint of whether the Serveris currently able to communicate to Devicesin the topology. “False” means that no communication is available.