Device to block unauthorized modem access over a PBX line
US5018190A · kind A · utility
30Cited by
6References
16Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 21, 1989 |
| Grant date | May 21, 1991 |
| Priority date | — |
| Expiry date | Sep 21, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M11/06
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A modem detector that enables detection of whether a modem is coupled to a phone line. When one is detected, various responses can occur, including: hanging up on the modem; checking if the modem linkage is allowable and, if it is not, then hanging up on the modem; and/or logging in the occurrence of an unauthorized modem access. To provide protection against unauthorized modem access, a digital embodiment can be used at the T1 phone line or an analog embodiment can be used after digital telephone data is converted into analog signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.