Method and apparatus for achieving transparent redundancy at a hierarchical boundary
US7269132B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 17, 2002 |
| Grant date | Sep 11, 2007 |
| Priority date | — |
| Expiry date | Aug 9, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L41/0663
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Transparent redundancy may be achieved at a MPLS-MPLS hierarchical boundary or a BMA-MPLS hierarchical boundary by utilizing local repair mechanisms extant in each domain to select automatically the same boundary network devices as the primary and secondary boundary network devices. In the MPLS domain, two LERs advertise the ability to forward traffic to a phantom LER and map all traffic originated into that domain as having been on a path originating at the phantom LER. This will cause the LERs to appear as being one hop away from the phantom LER, causing MPLS to assume the real LERs are part of a LSP terminating at the phantom LER. MPLS local repair will thus establish one of the LERs as the primary LER and the other LER as the secondary LER. In an Ethernet domain, each boundary network device is treated analogously to a router in the VRRP scheme for routers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.