Patent ID: 7376156

Claim:
A method of aligning clocks over multiple networks having different clock domains, comprising: transmitting timestamped packets over said networks between source and destination nodes via a plurality of intermediate nodes, said timestamped packets conveying timing information based on a source clock at said source node; determining the expected delay per node for said timestamped packets to traverse multiple nodes for a given traffic density; determining the chance of a timestamped packet not being delayed between said nodes; identifying a plurality of intermediate nodes between said source and destination node where the expected delay between said intermediate nodes and the chance of a packet not being delayed is such as to permit clock restoration within predefined acceptable parameters; restoring said clock at each said identified intermediate restoration node from the timestamped packets received at that 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; forwarding said new timestamped packets to said next intermediate node or said destination node when said new timestamped packets are produced from the last intermediate node.