Method and apparatus for routing and forwarding between virtual routers within a single network element

• US 20040233913A1
• Filed: 06/30/2004
• Published: 11/25/2004
• Est. Priority Date: 07/20/2002
• Status: Active Grant

• Current Assignee: Ericsson AB (Telefonaktiebolaget LM Ericsson)
• Original Assignee: Ericsson AB (Telefonaktiebolaget LM Ericsson)
• Inventors: Shen, Naiming
• Granted Patent: US 7,715,381 B2
• Time in Patent Office: Days
• US Class Current: 370/395.31
• 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 12/4679 Arrangements for the registration or de-registration of VLAN attribute values, e.g. VLAN identifiers, port VLAN membership
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 45/02 Topology update or discovery
• CPC Class Codes: H04L 45/033 by updating distance vector protocols
• CPC Class Codes: H04L 45/54 Organization of routing tables
• CPC Class Codes: H04L 45/586 of virtual routers
• CPC Class Codes: H04L 45/745 Address table lookup; Address filtering
• CPC Class Codes: H04L 45/76 Routing in software-defined topologies, e.g. routing between virtual machines

Abstract

A method and apparatus for routing and forwarding between virtual routers is described. A method in a single network element comprises peering a first virtual router to a second virtual router, wherein the first and second virtual routers have separate address spaces and separate routing tables, distributing a set of one or more routes from the first virtual router to the second virtual router, wherein a first of the set of routes identifies the first virtual router as a next hop of the first route, said first route including a destination, and downloading to a set of one or more forwarding tables, the destination and the next hop.

Claims

1. A method in a single network element comprising:

associating a first virtual router and a second virtual router to a virtual local area network (VLAN); and

indicating in a routing table a route from the first virtual router to the second virtual router via the VLAN.

2. The method of claim 1 wherein said associating comprises generating a first logical interface for the first virtual router that indicates the VLAN and a second logical interface for the second virtual router that indicates the VLAN.

3. The method of claim 2 wherein said first and second virtual routers exchange routing information via the first and second logical interfaces.

4. The method of claim 1 further comprising forwarding a packet to the second virtual router and a third virtual router from the first virtual router in accordance with an entry in the first virtual router'"'"'s forwarding table, which indicates a first logical interface as a next hop to the VLAN.

5. The method of claim 4 wherein the packet is received by the second virtual router via a second logical interface and the third virtual router receives the packet via a third logical interface, wherein said second logical interface identifies the second virtual router and the third logical interface indicates the third virtual router.

6. A machine-readable medium that provides instructions, which when executed by a set of one or more processors, cause said set of processors to perform operations comprising:

associating a first virtual router and a second virtual router to a virtual local area network (VLAN); and

indicating in a routing table a route from the first virtual router to the second virtual router via the VLAN.

7. The machine-readable medium of claim 6 wherein said associating comprises generating a first logical interface for the first virtual router that indicates the VLAN and a second logical interface for the second virtual router that indicates the VLAN.

8. The machine-readable medium of claim 7 wherein said first and second virtual routers exchange routing information via the first and second logical interfaces.

9. The machine-readable medium of claim 6 further comprising forwarding a packet to the second virtual router and a third virtual router from the first virtual router in accordance with an entry in the first virtual router'"'"'s forwarding table, which indicates a first logical interface as a next hop to the VLAN.

10. The machine-readable medium of claim 9 wherein the packet is received by the second virtual router via a second logical interface and the third virtual router receives the packet via a third logical interface, wherein said second logical interface identifies the second virtual router and the third logical interface indicates the third virtual router.