A communication system includes a HAVi-based in-home network 140 and a remote device 110 operative to communicate with an intermediate device 130 of the in-home network via Internet. The remote device loads a HAVi applet (Havlet) 238 for controlling at least one of the in-home devices using HAVi. The remote device also loads an HAVi API (HJA) emulator 310 which emulates HJA. The HJA emulator provides an interface for the Havlet and communicates with a module 330 in the intermediate device. The intermediate device includes the actual HJA 236 which provides the actual interface functionality for the HAVi functions used by the Havlet. The interface functionality is provided by controlling the intermediate device and/or communicating with other in-home device(s) according to application messages of the in-home application protocol. The intermediate device loads the module for enabling communication between the HJA emulator in the remote device and HJA loaded in the intermediate device, giving a substantially transparent communication path between the portable application program in the remote device and the HJA in the intermediate device.