Wifi – Is wireless wake on lan possible

You could use /etc/rc.local or some system boot scripts, but this wouldn't be the best way to do it. On startup your network interfaces are configured, sure, but there are other times when your network interfaces may be brought up or down and you will need this executed during those times.

You want to edit /etc/network/interfaces:

You should have a line like:

iface eth0 inet static

Underneath that, indented further, you want to create a post-up and post-down commands e.g.

iface eth0 inet static
    post-up /usr/sbin/ethtool -s eth0 wol g
    post-down /usr/sbin/ethtool -s eth0 wol g

Obviously, replace eth0 with the relevant interface if different.

See interfaces(5) for more information on post-up and post-down commands

man 5 interfaces

1) Wake up on LAN is a feature of the BIOS and network card:

Wake-on-LAN support is implemented on the motherboard (BIOS) of a computer and the network interface (firmware), and is consequently not dependent on the operating system (and NIC drivers) running on the hardware, although the operating system can sometimes control the Wake-on-LAN behaviour.

Source

2) The connection type of the machine sending the wake up signal shouldn't matter. As long as it is fully connected to the network they should be able to send the signal.

In case the computer being woken is communicating via Wi-Fi, the wake-up-packet can be sent via Wireless Multimedia Extensions (WMM)

3) There are tools to help you do this, though configuring the Server should just be a matter of setting up the BIOS correctly. The wake up is done by what Wikipedia calls a "Magic Packet" that contains the IP address of the server to be woken and the "wake-up" packet. This can be sent by any script/program that can access the network:

wolcmd 001122334455 10.0.0.2 255.255.255.255 7

(from the same Wikipedia page).

4) WOL does work over the Internet.