System and method to calculate round trip delay for real time protocol packet streams
AssigneeAgilent Technologies, Inc.
InventorWilliam Grant Grovenburg
Life of this patent
Estimating the term…
Abstract
An apparatus and method calculate a round-trip delay (RTD) between first and second endpoints within a network, where an intermediate point is selected between the first and second endpoints within the network. A network analyzer determines a first data transmission time from the intermediate point to the first endpoint and back to the intermediate point, determines a second data transmission time from the intermediate point to the second endpoint and back to the intermediate point, and adds the first and second data transmission times to determine therefrom the round trip delay between the first and second endpoints within the network.
Claims18
An apparatus to calculate a round-trip delay (RTD) between first and second endpoints within a network, where an intermediate point is selected between the first and second endpoints within the network, the apparatus comprising:
- a network analyzer determining a first data transmission time from the intermediate point to the first endpoint and back to the intermediate point, determining a second data transmission time from the intermediate point to the second endpoint and back to the intermediate point, and adding the first and second data transmission times to determine therefrom the round trip delay between the first and second endpoints within the network, wherein
- the first endpoint outputs a first signal,
- the network analyzer time stamps the first signal as Time1 at the intermediate point, and
- the second endpoint receives the first signal and outputs a second signal.
A method to calculate a round-trip delay (RTD) between first and second endpoints within a network, comprising:
- selecting an intermediate point between the first and second endpoints within the network;
- determining a first data transmission time from the intermediate point to the first endpoint and back to the intermediate point;
- determining a second data transmission time from the intermediate point to the second endpoint and back to the intermediate point;
- and
- adding the first and second data transmission times to determine therefrom the round-trip delay between the first and second endpoints within the network, wherein the determining of the first data transmission time comprises:
- outputting a first signal from the first endpoint;
- time stamping the first signal as Time1 at the intermediate point;
- receiving the first signal at the second endpoint;
- outputting a second signal from the second endpoint to the first endpoint;
- determining a first DLSR indicative of a delay between a time the second endpoint receives the first signal and a time the second endpoint outputs the second signal;
- time stamping the second signal as Time2 at the intermediate point;
- receiving the second signal at the first endpoint;
- and
- subtracting the Time1 and the first DLSR from the Time2 to determine therefrom the first data transmission time.
A method of a network analyzer connected at a point of analysis (POA) within a network between a source and a receiver, comprising:
- outputting a first signal from the source to the receiver;
- time stamping the first signal as Time1 at the POA;
- receiving the first signal at the receiver;
- outputting a second signal from the receiver to the source;
- determining a first DLSR indicative of a delay between a time the receiver receives the first signal and a time the receiver outputs the second signal;
- time stamping the second signal as Time2 at the POA;
- receiving the second signal at the source;
- and
- determining a first delay as follows:
- First delay=Time2−Time1−first DLSR.
Dependencies are inferred from the claim text.