Method and apparatus for dynamic adjustment of cable modem back-off parameters in a cable modem network
US6614799B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 20, 1999 |
| Grant date | Sep 2, 2003 |
| Priority date | — |
| Expiry date | Jan 20, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N7/17309
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A technique is provided for dynamically adjusting modem back-off parameters in a cable modem network. The technique is based on the theoretical result that the ratio of the number of the successful band width requests (Ns) to the number of collisions (Nc) has a value (e-31) when the back-off values are correctly estimated. The present technique for dynamically adjusting modem back-off parameters utilizes this concept to correspondingly correct the back-off parameters, depending upon the value of the Nc/Ns ratio, so as to cause this ratio to converge to the desired ratio of Nc/Ns equal to approximately 0.7. If the ratio of Nc/Ns is greater than a first specified value, the back-off start and backoff-end parameters (broadcast by the CMTS to cable modems on the downstream channel) are increased. If the ratio of Nc/Ns is less than a second specified value, the back-off start and backoff-end parameters are decreased. The present technique provides for improved access delay and improved throughput performance in contention sub-channels of cable access networks, particularly those involving large round trip delays. Additionally, the technique of the present invention utilizes elementary C…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.