PBX telephone call control system
US5325422A · kind A · utility
12Cited by
37References
1Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Nov 10, 1993 |
| Grant date | Jun 28, 1994 |
| Priority date | — |
| Expiry date | Nov 10, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M2215/745
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A PBX telephone call control system is disclosed. The system provides a line interface unit connection between a plurality of subscriber line extensions and a private branch exchange (PBX) switching equipment. The call control system appears to the PBX like any other telephone extension within the office environment and provides the user with more features in conjunction with the pre-existing PBX equipment, providing expanded capabilities at a reasonable expense.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.