Remote computer wake-up for network applications

A method for computer-based communication includes storing at a first computer records of correspondence between application-specific identifiers used in a network application and network addresses of computers on a network that are respectively associated with the application-specific identifiers. A second computer is powered down after storing at the first computer a record of the correspondence between an application-specific identifier and a network address associated with the second computer. If it is determined, while the second computer is powered down, that a message is to be directed by the network application to the application-specific identifier associated with the second computer, a wake-up packet is sent over the network to the network address specified by the record, so as to cause the second computer to power up and respond to the message.