Implied principal busy status indicator for covered calls
US4790004A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 10, 1986 |
| Grant date | Dec 6, 1988 |
| Priority date | — |
| Expiry date | Dec 10, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M3/546
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The subject implied principal busy status indicator provides all covering users with an indication of the busy/idle status of the principal's line on a covered call. This is accomplished by equipping each covering user's telephone station set with a principal busy status indicator for every line appearance on the covering user's telephone station set. When a covered call is diverted from a principal's line to the covering user's telephone station set, the line appearance on which the covered call appears is lighted and the principal busy status indicator associated with the covering user's line appearance indicates the busy/idle status of the principal's line. The business communication system updates the state of the principal busy status indicator so the covering user knows when the called principal's line is idle.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.