Patent ID: 8532482

Claim:
A method for detecting failures of a Passive Optical Network (PON) system, comprising: monitoring first performance-related information at an Optical Line Terminal (OLT), the first performance-related information comprising a variation of optical power measured at the OLT; determining whether the variation of the optical power measured at the OLT exceeds a preset threshold; requesting, when the variation of the optical power measured at the OLT exceeds the preset threshold, an Optical Network Unit (ONU) to report second performance-related information monitored at the ONU; and determining a failure of the PON system according to the first performance-related information monitored at the OLT and the second performance-related information monitored at the ONU; wherein the first performance-related information monitored at the OLT further comprises: a transmit optical power of an OLT laser, a bias current of the OLT laser, a driven current of the OLT laser, a receive optical power measured at the OLT, and an uplink bit error rate (BER) measured at the OLT; and the second performance-related information comprises: a transmit optical power of an ONU laser, a bias current of the ONU laser, a drive current of the ONU laser, a receive optical power measured at the ONU, and a downlink bit error rate (BER) measured at the ONU; wherein the determining the failure of the PON system according to the first performance-related information monitored at the OLT and the second performance-related information monitored at the ONU comprises: calculating an uplink optical attenuation and a downlink optical attenuation of an optical channel between the OLT and the ONU based on the first performance-related information and the second performance-related information; determining that a connection failure occurs when a difference between the downlink optical attenuation and the uplink optical attenuation is greater than a first predetermined value; and determining that a fiber bend occurs when the difference between the downlink optical attenuation and the uplink optical attenuation is less than a second predetermined value.