Time Synchronization Algorithm for Asymmetric Optical Fiber Communication Link

To solve the problem of delay asymmetry for IEEE 1588v2 implementation in a two-fiber bidirectional network, many methods have been proposed, such as the optical time-domain reflectometry method, the optical fiber switching method, and the singlefiber bidirectional transmission method, etc. However, none of the existing methods are suitable for an asymmetric optical fiber link with an optical amplifier or optical regenerator. We present a new time synchronization algorithm for IEEE 1588v2 to calculate the time offset in an asymmetric optical fiber link with an optical amplifier or optical regenerator. The new algorithm is based on the timestamp mechanism of IEEE 1588v2, and uses wavelength conversion to produce stamped messages, which are exchanged between the master and slave to enable the slave to calculate the time offset. The formula of the time offset between the master and slave is deduced, and the detailed steps and process are given. The new algorithm is not only suitable for a two-fiber bidirectional optical communication system, but also for the Wavelength Division Multiplexer system.