Take Control of Screen Sharing in Leopard

Sleep Causes Lack of Access

A computer can't be reached remotely when it's asleep, but a Mac can be woken remotely in some cases. You can also disable sleep mode. I explain both methods.

Enable remote wake ups

Mac OS X (and Windows) can be woken from a slumber through a bit of Sleeping Beauty magic. Rather than a prince's kiss, a specially formed packet sent to the right network port, whether sent over a local network or remotely, awakens the computer.

For this to work outside the local network, however, the computer in question must be connected to your local network via Ethernet and have a publicly routable IP address; you can also use a mapped port on a router for a single computer on the local network, but that computer still must be connected ...