Network monitoring system for cell delay variation
US5805602A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 1, 1996 |
| Grant date | Sep 8, 1998 |
| Priority date | — |
| Expiry date | Oct 1, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2012/5649
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An arrangement (apparatus and method) for monitoring jitter caused during transport of digitally-coded information in a packet switched network, and for managing network operations in accordance with the detected jitter. The detected jitter is used to determine whether corrective action is necessary, such as rerouting network traffic, or performing network maintenance. The disclosed arrangement detects program clock reference (PCR) values from an MPEG-encoded transport stream, whereby each pair of PCR values represents an expected arrival time of a corresponding stream segment. An actual arrival time for the corresponding stream segment is determined in response to detection of the corresponding PCR values and an independent clock signal. The expected arrival time of the stream segment and the actual arrival time are correlated with an accumulation of expected and actual arrivaimes of previously-received data packet stream segments in order to determine the jitter in the digital data stream. The jitter is corrected by a combination of adaptive buffering techniques and restamping the PCR value with corrected values coinciding with the actual arrival time of the stream segments.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.