Automatic backup trunking for voice over the internet
US6389005B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 1, 1997 |
| Grant date | May 14, 2002 |
| Priority date | — |
| Expiry date | Dec 1, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04Q3/62
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
To reduce telephone toll costs to a user, a PBX preferentially establishes a call to a destination number (DN) over a WAN or the internet. The PBX determines the available connection types available by querying look-up tables for the particular DN. If no alternatives to the PSTN are available, the call is routed over the PSTN. Where a WAN or internet connection is available, the call is then routed over this alternative service. If the Quality of Service (QoS) over the computer network connection falls below a specified threshold, a second parallel connection is made over the PSTN and the call is then transferred to the PSTN. The user is notified of this change in service. During the PSTN connection, the PBX polls the alternative service and, upon the QoS rising above a specified threshold, the call is then routed back to the alternative service and the PSTN connection is torn down. The user is again notified of this change in service.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.