Turn off Microsoft Peer-to-Peer Networking Services
This setting turns off Microsoft Peer-to-Peer Networking Services in its entirety, and will cause all dependent applications to stop working.
Peer-to-Peer protocols allow for applications in the areas of RTC, collaboration, content distribution and distributed processing.
If you enable this setting, peer-to-peer protocols will be turned off.
If you disable this setting or do not configure it, the peer-to-peer protocols will be turned on.
At least Windows XP Professional with SP2
In Registry Editor we can see the following changes:
For Enabled we get:
FullKeyPath : HKEY_LOCAL_MACHINE\Software\policies\Microsoft\Peernet
ValueName : Disabled
Value : 1