Detecting data plane liveliness of a label-switched path
US7463591B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 12, 2003 |
| Grant date | Dec 9, 2008 |
| Priority date | — |
| Expiry date | Nov 24, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L43/12
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Detecting if a label-switched path (LSP) is functioning properly. To test that packets that belong to a particular Forwarding Equivalence Class (FEC) actually end their MPLS LSP on an label switching router (LSR) that is an egress for that FEC, a request message carrying information about the FEC whose LSP is being verified may be used. The request message may be forwarded like any other packet belonging to that FEC. A basic connectivity test as well as a fault isolation test are supported. In a basic connectivity test mode, the packet should reach the end of the LSP, at which point it is sent to the control plane of the egress LSR. The LSR then verifies that it is indeed an egress for the FEC. In a fault isolation test mode, the packet is sent to the control plane of each transit LSR, which performs various checks that it is indeed a transit LSR for the LSP. The transit LSR may also return further information that helps check the control plane against the data plane, i.e., that forwarding matches what the routing protocols determined as the path. A reliable return path is used for the reply.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.