Method and apparatus for link state determination in voice over frame-relay networks
US6657970B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 26, 1999 |
| Grant date | Dec 2, 2003 |
| Priority date | — |
| Expiry date | Apr 16, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2012/6481
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for link state determination in voice over frame-relay networks. In one embodiment, the present invention includes a method for determining link state for permanent calls in an FRF.11 voice over data network at the virtual voice channel level. This is a capability not present in FRF.11, which includes a management mechanism for determining link state of virtual circuits, but no mechanism for determining link state of virtual channels. One embodiment uses a standard FRF.11 signaling frame with a status indicator bit to signal that a channel is a primary operative channel or an alternate operative channel. The signaling frames are sent end to end through the network by an initiator device along a primary data path and all alternate data paths. If a primary or alternate path is operative, a reciprocator device returns the signaling frame along the operative path. The initiator determines by receipt or non-receipt of the signaling frames which paths are operative at any time. This allows the initiator to quickly detect primary path failure and switch to an operative alternate path.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.