Method and apparatus for non-intrusive measurement of round trip delay in communications networks
US5521907A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 25, 1995 |
| Grant date | May 28, 1996 |
| Priority date | — |
| Expiry date | Apr 25, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2012/5649
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Measurement of round-trip delay or travel time in a communications network during in-service operation is accomplished by use of two probes, situated at respective points of interest along the communication network, and a processor. The probes receive identifiable data patterns normally transmitted over the communications network and generate a time stamp when each pattern arrives at or leaves the respective point. Each probe further generates a pattern identifier based on the data in the pattern and stores the identifier and time stamp as a pair in a buffer internal to each probe. Once the internal buffer contents exceed a predetermined amount of data, the processor receives the data from the buffers and matches pattern identifiers between the buffers to locate the departure and arrival time stamps of each pattern traveling between the probe points. Thereafter, the processor calculates an average of round-trip delay or travel times based on the departure and arrival time stamps of several patterns traveling in both directions between the probe points.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.