Hi, good people. The most use of WOL must be remotely from a phone running ARC. I have installed an app to do this job (with port-forwarding), and set the Win10 to auto sleep after 30 min of idle. Works like a charm.
But I wonder if it could be possible to build the WOL feature into the ARC app, like when you open it, it will send the magic packet in the same prosess, over the same port as the ARC itself are using (5000x)? Any thoughts?
I don’t think it can be done - at least not in a way that an ordinary user, with ordinary home routers could be expected to set up.
The socket (the (bidirectional) TCP point to point connection) between the Roon Servers will not be available when the Roon Server is sleeping so that cannot
WOL usually works as a broadcast on the local network of a magic packet containing the MAC address of the machine to be woken. The broadcast packet is usually done at the data link layer (layer 2 of the OSI model) and are thus at a layer below TCP/IP and so ip addresses cannot be used (and anyway, a sleeping computer may not have an ip address allocated).
It is possible to embed the magic in TCP or (more usually) UDP packets which which makes it possible, in theory, to use WOL from outside of the network but it may require some special router configuration that may not be available on comercial home routers - at least with their stock firmware.
Thx for your reply, Wade. Much appreciated 
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