Patent ID: 7787438

Claim:
A method of using two or more round trip measurements between a first and a second node in a network to estimate a delay parameter in traffic between the first and second node, each of the first and second nodes having a first and second clock respectively associated therewith, each measured round trip having timestamps associated therewith, the method comprising for each round trip measurement: a. shifting, by a processor, values of an upper bound and a lower bound for the clock offset in time difference between the first and second clocks by adding to the values of the upper and lower bounds an estimated long-term relative skew between the clocks since a previous round trip measurement; b. widening, by the processor, the upper and lower bounds by adding to the upper bound and subtracting from the lower bound a positive estimate of a maximum drift between the clocks since the previous round trip measurement; c. using, by the processor, the timestamps to lower the upper bound if the upper bound calculated from steps a) and b) is greater than an upper bound calculated using the timestamps; d. using, by the processor, the timestamps to increase the lower bound if the lower bound calculated from steps a) and b) is lower than a lower bound calculated using the timestamps; and e. using, by the processor, the upper and lower bounds from steps c) and d) in estimation of a one way delay measurement for traffic traveling unidirectionally between the first and second nodes, the one way delay measurement being attributed to a bounded one way directional delay element for traffic traveling in a direction from the first to the second node, a bounded one way directional delay element for traffic traveling in a direction from the second to the first node and a bounded delay element for delay whose attributed direction is indeterminate.