In a computer network including a plurality of interconnected computers,
one of the computers being a sleeping computer in a power down state, the
sleeping computer listening for a packet associated with the sleeping
computer, a method and system of waking the sleeping computer from the
computer network. An incoming packet of data is transmitted from one of
the computers in the network to the sleeping computer. When the sleeping
computer detects the incoming packet, it determines if the incoming
packet contains a data sequence associated with the sleeping computer.
Further, the sleeping computer compares a transit value in the incoming
packet to a predetermined value stored at the sleeping computer. The
transit value indicates how far the data packet has traveled through the
network, indicating the approximate origin of the data packet. Knowing
the approximate origin of the data packet allows the client system to
identify if the data packet originated from an external network. The
predetermined value represents an origin within the internal network.
Accordingly, if the incoming packet matches the particular data sequence
associated with the sleeping computer, and the transit value in the
packet matches the predetermined value stored at the sleeping computer,
then a signal is issued to wake the sleeping computer. Otherwise, the
incoming packet is discarded and the sleeping computer is not awaken.