Remote Desktop for Sleeping Computers
With Remote Desktop Connection (RDC), you can sit at a computer and connect to another computer in a different location (the remote computer). For example, you can sit at your home PC and connect to your work PC, and use all of your apps, files, and network resources as if you were sitting right in front of your work PC. The remote desktop feature is compatible with sleep mode in the Apple, Windows 7, Windows 8, and Windows 10 operating systems.
A client (desktop) computer must either be on or in sleep mode for remote access to work. In order to wake a computer from sleep mode for a remote desktop session, you’ll need to have the ARP (Address Resolution Protocol) offload and the NS (Neighbor Solicitation) offload features turned on (on the desktop’s network card.) These features allow the network card to maintain and renew the network address lease and routing information on behalf of the PC while the PC is in a low-power sleep state. With these features turned on, a user can connect to a sleeping computer just as he/she would if the machine were on.
The ARP offload and NS offload features differ from Wake on LAN (WOL): they make the PC addressable via its IP address and do not require that data be sent via “Magic Packet” to the broadcast address before getting routed to the sleeping host machine. Hence, when the ARP and NS offloads are active, a remote desktop connection can be made to a sleeping host in the same manner as a PC that is awake, with only an IP address.
The ARP offload and NS offload features are found on the advanced properties tab of the network card. They are typically turned on by default, so it’s really about determining whether the card has the features. Most computers manufactured since 2010 have cards with these features, and any network card based on nVIDIA NX1 or NX2 chip sets will have it as well.
Note that network card manufacturers may use slightly different names for these features, but the names are generally similar to “Address Resolution Protocol offload” and “Neighbor Solicitation offload” (e.g., “ARP Proxy”). You can always call the computer OEM or the network card vendor if you can’t locate the features.
Visit the following Microsoft webpages for additional information about remote access:
- Networking Power Management – features available in Windows 7.
- Microsoft Remote Desktop Clients – an overview
- Remote Desktop Connection FAQs – this link will detect the OS you're using, so make sure you access this link from the computer of interest. Note that this web page incorrectly states that, “you'll need to make sure the settings for sleep and hibernation are set to Never, since you can't connect to a PC that's asleep or hibernating.” This statement is false when ARP offload and NS offload features are turned on, and Energy Star has requested that Microsoft clarify it.