Abstract: Peer-to-peer communication is established between two remote computing units over a network channel, even though a permanent network address is not known. An originating computer sends a message over a monitor channel, such as a circuit-switched telephone line, to a receiving computer creating a triggering event. In response to the triggering event, either the originating computer or the receiving computer determines a network address associated with either the originating computer or the receiving computer. Then, using the network address, peer-to-peer communication between the originating computer and receiving computer is established over the network channel.