Method and system for discovering and providing near real-time updates of VPN topologies

• US 20070097991A1
• Filed: 10/31/2005
• Published: 05/03/2007
• Est. Priority Date: 10/31/2005
• Status: Abandoned Application

• Current Assignee: Agilent Technologies, Inc.
• Original Assignee: Agilent Technologies, Inc.
• Inventors: Tatman, Lance
• Application Number:
  US11/263,754
• Publication Number:
  US 20070097991A1
• Time in Patent Office: Days
• US Class Current: 370/395.53
• CPC Class Codes: H04L 12/4641 Virtual LANs, VLANs, e.g. virtual private networks [VPN] LAN interconnection over a bridge based backbone H04L12/462; encapsulation techniques H04L12/4633; routing of packets H04L45/00; packet switches H04L49/00; virtual private networks for security H04L63/0272
• CPC Class Codes: H04L 12/4675 Dynamic sharing of VLAN information amongst network nodes configuration of the network or of network elements H04L41/08
• CPC Class Codes: H04L 41/12 Discovery or management of network topologies
• CPC Class Codes: H04L 41/122 of virtualised topologies, e.g. software-defined networks [SDN] or network function virtualisation [NFV]
• CPC Class Codes: H04L 45/04 Interdomain routing, e.g. hierarchical routing
• CPC Class Codes: H04L 45/50 using label swapping, e.g. multi-protocol label switch [MPLS]

Abstract

Each provider edge router in a provider network connected to one or more VPNs is identified. Each identified provider edge router is then queried to obtain VPN configuration and VPN policy information for each VPN configured on that edge router. Routing protocol messages, such as, for example, Border Gateway Protocol/Multiprotocol Label Switching (BGP/MPLS) and Interior Gateway Protocol (IGP) messages, are then collected from the provider network. Using the discovered policies and topology information, VPN routing information carried in the routing protocol messages can be used to update VPN topology and status information in near real-time.

Claims

1. A system for maintaining near real time topology for one or more virtual private networks (VPNs) associated with a provider network, the system comprising:

one or more routers connected to at least one VPN; and

a network monitoring unit operable to determine a topology for each VPN using topology information associated with each VPN, wherein the topology information comprises a routing policy for each router connected to a VPN.

2. The system of claim 1, wherein the one or more routers connected to at least one VPN comprise provider edge routers.

3. The system of claim 2, further comprising one or more provider routers.

4. The system of claim 3, wherein the network monitoring unit is connected to all of the provider and provider edge routers.

5. The system of claim 3, further comprising a route reflector connected to the network monitoring unit, all of the provider edge routers, and all of the provider routers.

6. A system for maintaining near real time topology for one or more virtual private networks (VPNs) in a provider network, the system comprising:

a provider edge router connected to a VPN;

a network monitoring unit operable to determine the topology of the VPN using topology information associated with the VPN, wherein the topology information comprises a routing policy for the provider edge router.

7. The system of claim 6, further comprising a provider router.

8. The system of claim 7, wherein the network monitoring unit is connected to all of the provider routers and provider edge routers.

9. The system of claim 7, further comprising a route reflector connected to the network monitoring unit, the provider edge router, and the provider router.

10. A method for determining a topology for one or more virtual private networks (VPNs), comprising:

identifying each router connected to the one or more VPNs;

obtaining topology information associated with each VPN to determine the one or more routes in each VPN, wherein the topology information comprises a routing policy for each VPN; and

constructing a routing table for each VPN.

11. The method of claim 10, further comprising identifying a router type for each router.

12. The method of claim 11, wherein the router type comprises one of a provider router and a provider edge router.

13. The method of claim 12, wherein identifying each router connected to the one or more VPNs comprises identifying each provider edge router that provides an entrance point or an exit point to the one or more VPNs.

14. The method of claim 13, wherein identifying each provider edge router that provides an entrance point or an exit point to the one or more VPNs comprises identifying each provider edge router that provides an entrance point or an exit point to the one or more VPNs using Multiprotocol Label Switching label-switched path (LSP).

15. The method of claim 12, wherein identifying each router connected to the one or more VPNs comprises determining each router transmitting a Border Gateway Protocol (BGP) extended update message.

16. The method of claim 12, wherein identifying each router in the provider network connected to the one or more VPNs comprises:

determining each router in the provider network that transmits messages using BGP; and

determining each provider edge router from the one or more routers that transmit messages using BGP.

17. The method of claim 16, wherein determining each router in the provider network that transmits messages using BGP comprises performing a recursive Simple Management Network Protocol (SMNP) lookup using a BGP management information base (MIB).

18. The method of claim 16, wherein determining each provider edge router from the one or more routers that transmit messages using BGP comprises querying each BGP router to obtain identifying information associated with each VPN.

19. The method of claim 10, further comprising updating the routing table for each VPN.

20. The method of claim 10, further comprising determining an internal topology for a provider network.