Computer communications control
US4475175A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 29, 1982 |
| Grant date | Oct 2, 1984 |
| Priority date | — |
| Expiry date | Jan 29, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG07C9/33
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A secure communication link is provided for transmitting signals between a host computer and at least one authorized terminal. The communication link includes a host modem for modulating and demodulating the signals transmitted between the host computer and the authorized terminal and an access controller. The access controller stores enquiry and reply sequences of bits and is operable to compare incoming signals from the host modem with the stored sequences of bits. Where there is agreement between the signals from the host modem and the stored sequences of bits, the controller establishes the communication link. Where there is no agreement or no reply from the host modem, the controller disconnects the host modem from the link.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.