Advanced Monitoring of PONs

New integrated monitoring concepts for physical layer supervision of optical access networks are presented. Simple remotely controlled integrated measurement systems will help network operators to improve network quality and reliability and to save operational costs. Introduction The increasing amount of optical fiber connections in access and metro networks and the growth of sensitive and time critical data contents force the network operators to ensure the network availability and reliability. Most of the network faults are based on failures on the physical layer. New efficient and inexpensive means to monitor the performance and status of the optical network infrastructure on the physical layer are needed to enable preventive maintenance activities. Ubiquitous and early detection of degrading performance shall help the network operators to minimize their operational expenses. After years of developing new cost effective concepts to transmit higher amounts of data with optical networks the network operator's focus is changing from the CAPEX view to the OPEX view now. Today preventive maintenance without affecting service is absolutely necessary in long haul transmission networks to ensure the network availability. The increasing amount of optical fiber links in access and metro networks provoke network operators to ask for efficient and inexpensive means to keep the performance and status of their optical network on the physical layer under surveillance, remotely and automatically.