A remotely powered OTDR node, placeable at any location within the ODN, is introduced and a possible node architecture to overcome the ambiguity behind PON power splitters is given. First measurements show the feasibility of this approach.

We demonstrate an intelligent symmetric-rate 8- x 10-Gb/s bidirectional time and wavelength-division multiplexed passive optical network with 42-km reach and 1: 256 split 1425-nm laser pump light provides distributed Raman amplification for the upstream channels (allowing low-cost low-power transmitters), serves as a low-rate telemetry channel, and powers an intelligent splitter module that provides supervision for mission-critical services

Modern optical distribution networks will require performance measurements and reconfiguration functions in future. These measurement functions will provide the infrastructure owner information about the health of the network at any time. New reconfiguration functions will increase the speed of network modifications and network recovery in case of malfunctions. Operation and maintenance tasks will be supported and simplified by these new functions. One major reason why these functions are not installed today is the energy provision in unpowered nodes of the network. A remote optical powering approach is presented to establish new elements for a fiber infrastructure management system in the optical access domain.

We demonstrate a symmetric-rate, 8 x 10-Gb/s, bi-directional TWDM-PON with 42-km reach, and 1:256 split. Distributed Raman amplification provides gain for the upstream channels (allowing low-cost low-power transmitters) and powering for an intelligent splitter module that provides supervision for mission-critical services.

In this paper we describe and demonstrate a new remote in-service monitoring technique for passive optical access networks. New microwatt off-grid powered devices are introduced that may be installed at any location in the network. These monitors are equipped with a unique software-defined address, allow status monitoring of network parameters, facilitate the integration of remote active elements such as switches, and scale up easily to thousands of devices. Such monitors may be used to identify and measure the power levels and connection availability of a customer's site independent of the subscribers' optical network termination (ONT). Even physical disconnection of a rogue or erroneous ONT is demonstrated. A hardware implementation using off-the-shelf components together with a special communication protocol was successfully demonstrated in a gigabit passive optical network (GPON) testbed, where random data were transmitted. The lowest power consumption with less than 2 μW allows for powering with an optical supply channel or a small battery that lasts for a decade.

In a passive optical network, network availability as well as network security will become increasingly important. Traffic-transparent energy-autarkic supervision units located at demarcation points between network segments (so-called demarcation devices, DD) would fill this need. The DD respond to a low-duty cycle low-bitrate control signal which the operator¿s central office (CO) superimposes to the optical data stream sent to the subscribers. Most of the time the DD stay in a low-energy sleep mode, but awake during very short time intervals for communicating with the CO. In sleep mode, synchronism with the CO is lost. Our new low-energy medium-access control (LE-MAC) protocol assures a fixed ¿rendezvous¿ time where all DD can individually respond to the CO. In a small network we show the feasibility of the concept and the functionality of the LE-MAC protocol. The mean current consumption of a DD is less than 1 muA corresponding to 3 muW. With a single inexpensive lithium ion battery, such a DD could operate for more than 10 years.

We present recent advances in low cost fiber monitoring techniques for FTTH/FTTB networks employing integrated means for localizing fiber faults and for testing fiber connectivity in PONs.

New integrated monitoring concepts for physical layer supervision of optical access networks are presented. Network faults and outage times are mainly originated by drifts and degradations of parameters on the physical layer. Simple remotely controlled integrated measurement systems will help network operators improve network quality and reliability and save operational costs. In addition to supervision under the performance parameters of active network components, the optical fiber plant itself will be supervised by an embedded fiber monitoring system in future. We present the functionality of a demarcation point monitor as a new network element which provides information about network availability up to the home network. The operation and the performance parameters of the new monitoring systems are described, and the compatibility with the transmission system is shown in detail. Finally, the additional expenditures and the benefits for the operator are discussed. © 2008 Alcatel-Lucent.