This policy setting changes the operational behavior of the Mapper I/O network protocol driver. LLTDIO allows a computer to discover the topology of a network it's connected to. It also allows a computer to initiate Quality-of-Service requests such as bandwidth estimation and network health analysis. The recommended state for this setting is: Disabled. Rationale: To help protect from potentially discovering and connecting to unauthorized devices, this setting should be disabled to prevent responding to network traffic for network topology discovery. Impact: None - this is the default behavior.
To establish the recommended configuration via GP, set the following UI path to Disabled: Computer Configuration\Policies\Administrative Templates\Network\Link-Layer Topology Discovery\Turn on Mapper I/O (LLTDIO) driver Note: This Group Policy path is provided by the Group Policy template LinkLayerTopologyDiscovery.admx/adml that is included with all versions of the Microsoft Windows Administrative Templates. Default Value: Disabled. (The Mapper I/O (LLTDIO) network protocol driver is turned off.)