Protected information transfer system
US4949334A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 21, 1989 |
| Grant date | Aug 14, 1990 |
| Priority date | — |
| Expiry date | Apr 21, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L12/40013
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
An add/drop interface is connected in series with a data bus and is constructed for receiving an add/drop module. The add/drop interface includes a data selection multiplexer which receives through data from the data bus and add/drop from the module and selects the proper output data in response to a signal received from a controller in said interface. The controller provides a signal to drive the data selection multiplexer to select the add/drop data only after all transient signals resulting from module connection have dissipated. The controller also provides error checking so that the through data is selected if errors are detected. Timing circuitry in the interface maintains the correct phase relationship between through data and add/drop data.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.