Patent · US Expired

Hitless protection switching

US7193964B2 · kind B2 · utility

5Cited by
3References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 22, 2002
Grant dateMar 20, 2007
Priority date
Expiry dateJan 18, 2025

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04J2203/0094
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

The invention provides a method and apparatus for providing hitless protection switching in a transmission systems which support a standardized implementation of virtual concatenation. A switching apparatus is arranged to receive data signals on at least two transmission paths and to output data from a selected one of said transmission paths. The apparatus is arranged to align the respective received data signals so that a selector mechanism can select between corresponding elements of the received data signals. This arrangement allows hitless switching to be performed since there is no loss or repetition of signal elements when switching occurs. In a preferred embodiment, data in respect of each frame of each data signal is stored and the selector mechanism selects between paths on a frame-by-frame basis by comparing quality information carried by the data signals. This arrangement offers a very low end to end Bit Error Rate (BER) performance. The invention is suitable for both synchronous and non-synchronous networks (for example, OTN) which implement standardized virtual concatenation.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.