Line switching apparatus
US5754527A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 20, 1996 |
| Grant date | May 19, 1998 |
| Priority date | — |
| Expiry date | Mar 20, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2012/5681
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A line switching apparatus is applied to a system which has a current system line and a spare system line, transmits identical ATM cell streams via the two lines, and adds protection switching cells to the ATM cell streams on a transmission side when line quality of the current system line deteriorates. The apparatus is adapted to switch a line to be used from the current system line to the spare system line in the system. The apparatus includes a first VPI converter, a multiplexer, a spare system line information read section, and a second VPI converter. The first VPI converter converts the VPI of the spare system line into a VPI different from the VPI of the current system line. The multiplexer detects a phase shift amount between the current and spare system lines on the basis of positions of the protection switching cells on the two lines, corrects the phase shift amount, and performs multiplexing processing of packing the cell stream on the spare system line, whose VPI has been converted, at empty cell positions of the cell stream on the current system line. The read section reads out the information of the spare system line from the multiplexed cell stream. The second VPI con…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.