Photonwares produces net-ready Optical Line protection (OLP) switches uniquely featuring ultra-fast switch (<100ns) so that minimum data will be lost in the event of a fiber link failure. OLP enhances and secures the reliability of an optical network by using two routes in which one is active and another a redundant standby fiber line. OLP is used in pairs with two identical units, one at each end of the optical network transmission line. It has optical tap detectors constantly monitoring the optical power of the data transmission. In case the optical power inside the active fiber gets lower than a user-defined threshold, the OLP automatically switches the link to go through the standby fiber, restoring the communication and services. The switching module is available in a standard 1U rackmount with up to four Pluggable Modules. Larger racks to house a large number of pluggable modules are available. Special control algorism, wavelengths, connectors can be customized to meet and applications. We further offer built-in amplifiers for long-distance links. Photonwares provides two types of line protection: 1:1 and 1+1. The features of these configurations are detailed below.
OLP configuration 1:1, as shown in the diagram below, consisting of the main fiber route and a standby fiber route between the two sites and associated fiber optical switches. In normal operation, the data are transmitted and received through the main route. Inside the OLP pair, detectors are incorporated at Rx ports to detect the decreasing of the optical power. When a fault is detected on the main route, the system will switch both the transmitting and receiving from the main route to the standby route. This is accomplished by first turn off the build-in test laser so that both ends detect fault. The advantages of 1:1 OLP system are low optical insertion loss with direct signal passthrough, and the optical fiber for the backup path can also be used for other business. The disadvantage is conventional systems require CPU processing the information at both ends, resulting in typically delays of about 80ms in response.
OLP 1+1 configuration is shown in the following diagram, in which the optical signals are split into two with a ratio of 50:50 and transmit through both main and standby routes at the same time. While for Rx, the optical signal with better quality will be selected when a fault is detected. The advantage of OLP 1+1 system is faster recovering optical switching. We offer 100ns recovering option in this configuration. However, there will be larger insertion loss compared with the OLP 1:1 system.