Scalable and fault-tolerant link state routing protocol for packet-switched networks

• US 7,583,603 B2
• Filed: 07/13/2004
• Issued: 09/01/2009
• Est. Priority Date: 11/30/2000
• Status: Active Grant

• Current Assignee: Parity Networks LLC
• Original Assignee: Pluris, Inc
• Inventors: Akyol, Bora, Agarwal, Puneet, Ginsberg, Les
• Primary Examiner(s): PHAN, MAN U
• Application Number:
  US10/891,349
• Publication Number:
  US 20040258065A1
• Time in Patent Office: 1,876 Days
• Field of Search: 370238-254, 370389-392, 370400-465, 709201-239, 709242-248, 714 4- 13
• US Class Current: 370/238
• CPC Class Codes: H04L 41/0663 Performing the actions predefined by failover planning, e.g. switching to standby network elements
• CPC Class Codes: H04L 41/0803 Configuration setting
• CPC Class Codes: H04L 43/0811 by checking connectivity
• CPC Class Codes: H04L 43/0817 by checking functioning
• CPC Class Codes: H04L 45/04 Interdomain routing, e.g. hierarchical routing
• CPC Class Codes: H04L 45/12 Shortest path evaluation
• CPC Class Codes: H04L 45/586 of virtual routers
• CPC Class Codes: H04L 45/60 Router architectures
• CPC Class Codes: H04L 49/555 Error detection
• CPC Class Codes: H04L 69/40 for recovering from a failure of a protocol instance or entity, e.g. service redundancy protocols, protocol state redundancy or protocol service redirection management of faults, events, alarms or notifications in data switching networks H04L41/06

Abstract

A distributed Link-State Routing Protocol (LSRP) system in a packet switch having external communication ports has a first card executing Update process of the LSRP, making database updates, a second card executing Decision process(Shortest Path First (SPF)) of the LSRP, and a communication fabric coupling the cards with each other and the external ports. The LSRP may be an IS-IS system. In some embodiments there are additional cards involved, and the distribution of Link-State functions is over a set of multiple cards. Also in some embodiments there is a Location Service (LS) controller monitoring and configuring cards in the system.

Claims

1. A distributed Link-State Routing Protocol (LSRP) system in a packet switch having external communication ports, comprising:

a first card;

a second card;

a third card;

a communication fabric coupling the cards with each other and the external ports; and

a location service (LS) controller operating external to the LSRP-related processes on the cards configuring and monitoring the LSRP system;

wherein the LS controller configures one of the three cards to execute an update process of the LSRP, making database updates, another to execute a Decision (Shortest Path First (SPF)) process of the LSRP, and the third to act as a backup, and reassigns roles according to monitored condition of the three cards the first card updates both the second and third cards.

2. The system of claim 1 wherein the LSRP is one of an Intermediate System to Intermediate System (IS-IS) LSRP, or an Open Shortest Path First (OSPF) LSRP.

3. A packet switch, comprising:

a plurality of cards, some of which have one or more communication ports;

a first card;

a second card;

a third card;

a communication fabric coupling the cards; and

a location service (LS) controller operating external to the LSRP-related processes on the cards configuring and monitoring the LSRP system;

wherein the LS controller configures one of the three cards to execute an update process of the LSRP, making database updates, another to execute a Decision (Shortest Path First (SPF)) process of the LSRP, and the third to act as a backup, and reassigns roles according to monitored condition of the three cards the first card updates both the second and third cards.

4. The packet switch of claim 3 wherein the LSRP is one of an Intermediate System to Intermediate System (IS-IS) LSRP or an Open Shortest Path First (OSPF) LSRP.

5. A method for distributing a Link-State Routing Protocol (LSRP) in a packet switch having at least three cards for executing an LSRP process, comprising the steps of:

(a) providing a location service (LS) controller for operating external to the cards executing the LSRP process, wherein the LS controller configures and monitors the LSRP system;

(a) configuring one of the three cards by the LS controller to execute an update process of the protocol;

(b) configuring another of the three cards by the LS controller execute Decision process(Shortest-Path First (SPF)) of the protocol;

(c) configuring the remaining card to act as a backup;

(d) executing the configured functions on the cards, and synchronizing copies of a the Adjacency, Circuit, and Link State databases on the cards; and

(e) reassigning roles by the LS controller according to monitored condition of the three cards.

6. The method of claim 5 wherein the LSRP is one of an Intermediate System to Intermediate System (IS-IS) LSRP or an Open Shortest Path First LSRP.

7. The method of claim 5 wherein two or more cards are configured to execute the Update functions of the protocol.