Alignment of clocks over multiple packet networks

Abstract

Disclosed is a method of aligning clocks over multiple networks having different clock domains. The method comprises transmitting timestamped packets over said networks between source and destination nodes, said timestamped packets conveying timing information based on a source clock at said source node, determining the expected delay over multiple nodes for a given traffic density, identifying at least one intermediate node between said source and destination node where said determined expected delay is such as to permit clock restoration within predefined acceptable parameters, restoring said source clock at said at least one intermediate restoration node to generate a restored intermediate clock signal, producing from said restored intermediate clock signal new timestamped packets conveying timing information based on said restored intermediate clock signal, and forwarding said new timestamped packets to said destination node.