A point-to-point (P2P) apparatus has a device resource, a processor, a storage device and a network interface. The processor processes the device resource. The storage device stores a unique identification code. The network interface connects to a first network via a first gateway and transmits the unique identification code to a server via a second network by a first gateway. An external device accesses the device resource via the first gateway. The second network is a TCP/IP network and the first network is not a TCP/IP network.