This policy setting changes the operational behavior of the Responder network protocol driver.The Responder allows a computer to participate in Link Layer Topology Discovery requests so that it can be discovered and located on the network. It also allows a computer to participate in Quality-of-Service activities such as bandwidth estimation and network health analysis.If you enable this policy setting additional options are available to fine-tune your selection. You may choose the "Allow operation while in domain" option to allow the Responder to operate on a network interface that's connected to a managed network. On the other hand if a network interface is connected to an unmanaged network you may choose the "Allow operation while in public network" and "Prohibit operation while in private network" options instead.If you disable or do not configure this policy setting the default behavior for the Responder will apply.
Network\Link-Layer Topology Discovery
At least Windows Vista
HKLM\Software\Policies\Microsoft\Windows\LLTD!EnableRspndr; HKLM\Software\Policies\Microsoft\Windows\LLTD!AllowRspndrOnDomain HKLM\Software\Policies\Microsoft\Windows\LLTD!AllowRspndrOnPublicNet HKLM\Software\Policies\Microsoft\Windows\LLTD!ProhibitRspndrOnPrivateNet