Ring transmission system
US5159595A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 20, 1988 |
| Grant date | Oct 27, 1992 |
| Priority date | — |
| Expiry date | Dec 20, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2012/5612
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A transmission system comprises nodes coupled in a ring via two multiplexed transmission paths having opposite transmission directions. The two paths can be time, space, or wavelength division multiplexed. Bidirectional communications between any two nodes are provided in normal operation using both paths around a first, most direct, part of the ring. In the event of a fault affecting such communications, a protection switch is made to maintain bidirectional communications between the two nodes using both paths around a second, remaining, part of the ring. In this manner, each path can simultaneously carry both normal and protection switched signals. In an embodiment of the invention, only the two nodes adjacent a fault need be aware of the fault, each of these nodes effecting a protection switch for signals terminated at the node and effecting a protective loopback for other signals needing protection. The invention enhances the total capacity of the paths for carrying normal and protection switched signals. A network may comprise a plurality of such ring transmission systems intersecting at at least one network node, the network node comprising a node of each ring and a cross con…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.