Policy-based forwarding in open shortest path first (OSPF) networks
US7831733B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 6, 2001 |
| Grant date | Nov 9, 2010 |
| Priority date | — |
| Expiry date | Apr 29, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L45/033
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A method and system enables policy-based traffic forwarding in a data network by implementing policy-based control over propagation of LSA messages through the data network. A route tag is asserted in respect of a link state advertisement (LSA) message advertising a network address. Propagation of the LSA through the data network is controlled using the asserted internal route tag. At each hop, a policy decision affecting the forwarding of the LSA is made. Exemplary policy decisions include, Pass and Discard. In addition, the forwarding table may be updated using the route and address information contained in the LSA. In this case, routes entered in the forwarding table may be tagged as an inclusion route or an exclusion route. This may be based on the value of an exclusion route flag, which can, for example, be provided as a binary “0” or “1” inserted into an unused portion of the options field of the LSA.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.