Fast convergence with topology switching
US6678241B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 30, 1999 |
| Grant date | Jan 13, 2004 |
| Priority date | — |
| Expiry date | Nov 30, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L41/0663
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A system for rapidly switching at least one virtual local area network (VLAN) from a first loop-free topology to a second loop-free topology in response to a failure within the first loop-free topology. Each VLAN has one “logical” VLAN which represents the network entities organized into the VLAN and a set of “physical” VLANs each having its own VLAN designation. For each physical VLAN, a different loop-free topology is defined, although only one physical VLAN is “active” at any given time. Messages associated with the logical VLAN are tagged with the designation of the currently active physical VLAN, and forwarded along its loop-free topology. Upon detecting a failure in the loop-free topology, the logical VLAN is rapidly switched to the loop-free topology defined by a second, back-up physical VLAN. Following the switch messages associated with the logical VLAN are tagged with the designation of this back-up VLAN and are forwarded along its loop-free topology.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.