Systems and methods for synchronizing backup receivers to network clocks

Abstract

An interworking function (IWF) at an edge of a packet network comprises a primary receiver and a backup receiver. The primary receiver receives data packets and timing information from a packet network. The primary receiver interworks data from the data packets into a data signal that is based on a local clock signal. The primary receiver uses the timing information from the packet network to adjust the frequency of the local clock signal such that it is synchronous to a network clock signal, such as a clock signal at an IWF, referred to as the 'transmitting IWF,' that transmitted the data packets. In addition, the primary receiver from time-to-time provides timing information, such as a frequency control word, to the backup receiver, which uses such timing information to synchronize a clock signal of the backup receiver to the network clock signal upon an occurrence of a switchover from the primary receiver to the backup receiver. By using the timing information from the primary transceiver, the backup transceiver is able to synchronize its clock signal to the network clock signal in less time.