Next-generation passive optical networks (PONs) will, in most cases, leverage existing outdoor plant infrastructure. Adding new services on existing networks translates into overlaying multiple wavelengths on the same physical fiber plant. The PPM1 is compatible with multiple services including GPON, EPON, XGS-PON and 10G-EPON technologies. Its wavelength-selective design allows it to measure up to two downstream signals simultaneously, assessing power level for rapid and reliable service activation.