Shared Metallic Path Facility (SMPF)
Shared Metallic Path Facility is the shared form of local loop unbundling, in which one provider offers broadband over a line while another (or the same) provider supplies the voice service.
What is Shared Metallic Path Facility (SMPF)?
SMPF splits the frequencies on the copper line: the lower band carries analogue voice and the higher band carries broadband. It is "shared" because two services, possibly from different providers, use the same physical line.