Distinctive dial tone for a VoIP call
US7593389B2 · kind B2 · utility
16Cited by
4References
41Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Sep 3, 2004 |
| Grant date | Sep 22, 2009 |
| Priority date | — |
| Expiry date | May 14, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M3/42017
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A VoIP analog telephone adapter coupled to a telephone allows a telephone call to be made over the Public Switched Telephone Network (PSTN) or over the Internet. Prior to dialing a phone number, with the telephone “off-hook”, a caller receives an audible indication as to whether the call will be made over the PSTN or the Internet through a standard dial tone generated by a Central Office or a distinctive dial tone generated by the adapter. The distinctive dial tone is different from the PSTN's dial tone.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.