Patent ID: 7023816

Claim:
A method of synchronizing a timing device of a client station comprising the steps of: a) sending a plurality of packets, each packet being sent at a predetermined time and having a predetermined temporal spacing from other packets, from a time server to the client station via a communications network having unknown transmission time variations; b) receiving the plurality of packets at the client station; c) determining a time indicative of a local time of receipt of each packet of the plurality of packets at the client station and storing time data in dependence thereon; d) returning the plurality of packets to the time server via the communications network; e) determining a time indicative of a local time of receipt of each packet of the plurality of packets at the time server; and, f) determining synchronization data in dependence upon round trip delay of the packets and in dependence upon variance in temporal spacing of received packets relative to the predetermined temporal spacing, the synchronization data relating to an estimate of a minimum travel time of a packet between the time server and the client station via a communications network having unknown transmission time variations that are significant relative to the minimum travel time, wherein each packet comprises a binary signal of m bits, the binary signal comprising an identifier of the packet and an identifier of the time server.