MULTICAST MULTIPATHING IN AN OVERLAY NETWORK

• US 20170214619A1
• Filed: 04/07/2017
• Published: 07/27/2017
• Est. Priority Date: 11/05/2013
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Edsall, Thomas J., Yadav, Navindra, Chu, Kit Chiu, Doddapaneni, Krishna, Matus, Francisco M., Sinha, Satyam, Merchant, Sameer
• Granted Patent: US 10,623,206 B2
• Time in Patent Office: Days
• CPC Class Codes: H04L 12/18 for broadcast or conference , e.g. multicast
• CPC Class Codes: H04L 12/4633 Interconnection of networks using encapsulation techniques, e.g. tunneling
• 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 12/4645 Details on frame tagging routing of packets H04L45/00; support for virtual LAN H04L49/354
• CPC Class Codes: H04L 2212/00 Encapsulation of packets
• CPC Class Codes: H04L 41/0654 using network fault recovery ring fault isolation or reconfiguration in loop networks without recovery actions by a network management system H04L12/437
• CPC Class Codes: H04L 43/0811 by checking connectivity
• CPC Class Codes: H04L 43/0852 Delays
• CPC Class Codes: H04L 43/0894 Packet rate
• CPC Class Codes: H04L 43/16 Threshold monitoring
• CPC Class Codes: H04L 45/02 Topology update or discovery
• CPC Class Codes: H04L 45/021 Ensuring consistency of routing table updates, e.g. by using epoch numbers
• CPC Class Codes: H04L 45/16 Multipoint routing
• CPC Class Codes: H04L 45/22 Alternate routing
• CPC Class Codes: H04L 45/24 Multipath
• CPC Class Codes: H04L 45/245 Link aggregation, e.g. trunking
• CPC Class Codes: H04L 45/28 using route fault recovery
• CPC Class Codes: H04L 45/48 Routing tree calculation
• CPC Class Codes: H04L 45/50 using label swapping, e.g. multi-protocol label switch [MPLS]
• CPC Class Codes: H04L 45/64 using an overlay routing layer
• CPC Class Codes: H04L 45/74 : Address processing for routing
• CPC Class Codes: H04L 45/745 : Address table lookup; Address filtering
• CPC Class Codes: H04L 45/7453 : using hashing
• CPC Class Codes: H04L 47/125 : by balancing the load, e.g. traffic engineering
• CPC Class Codes: H04L 49/70 : Virtual switches
• CPC Class Codes: H04L 51/214 : using selective forwarding
• CPC Class Codes: H04L 61/2503 : Translation of Internet protocol [IP] addresses
• CPC Class Codes: H04L 61/2592 : using tunnelling or encapsulation
• CPC Class Codes: H04L 67/10 : in which an application is distributed across nodes in the network software deployment G06F8/60; multiprogramming arrangements G06F9/46
• CPC Class Codes: H04L 69/22 : Parsing or analysis of headers

Abstract

The subject technology addresses a need for improving utilization of network bandwidth in a multicast network environment. More specifically, the disclosed technology provides solutions for extending multipathing to tenant multicast traffic in an overlay network, which enables greater bandwidth utilization for multicast traffic. In some aspects, nodes in the overlay network can be connected by virtual or logical links, each of which corresponds to a path, perhaps through many physical links, in the underlying network.

Claims

1. A system, comprising:

one or more processors;

a network interface coupled to the one or more processors; and

a non-transitory memory coupled to the one or more processors, the memory including instructions that, when executed by the processors, cause the processors to execute operations comprising;

receiving, over the network interface, a multicast packet for distributing to a set of receivers in an overlay network;

performing a hash operation on at least a portion of the multicast packet to determine a hash key;

selecting a forwarding tag (FTAG) value based at least on the hash key, wherein the FTAG value is associated with a multicast distribution tree in the overlay network; and

concatenating an overlay multicast group value with the FTAG value to provide a destination address.

2. The system of claim 1, wherein the processors are further configured to perform operations comprising:

encapsulating the multicast packet with the concatenated overlay multicast group value and the FTAG value; and

forwarding the encapsulated multicast packet to a network element located at a next-hop in the overlay network.

3. The system of claim 1, wherein the multicast packet is received by a virtual extensible local area network (VXLAN) tunnel end point (VTEP) in the overlay network.

4. The system of claim 1, wherein the hash operation is performed on at least one of an IP destination address or an IP source address in an IP header of the multicast packet, information in an layer 2 (L2) header, or information in the multicast packet indicating a UDP port number or a TCP port number.

5. The system of claim 1, wherein the FTAG value is associated with a multicast distribution tree selected from a plurality of multicast distribution trees in the overlay network.

6. The system of claim 1, wherein the overlay multicast group value comprises an overlay multicast group address.

7. The system of claim 6, wherein the FTAG value comprises a lower four bits of a header field including the concatenated overlay multicast group value and the FTAG value.

8. A computer-implemented method, comprising:

receiving, over a network interface, a multicast packet for distributing to a set of receivers in an overlay network;

performing a hash operation on at least a portion of the multicast packet to determine a hash key;

selecting a forwarding tag (FTAG) value based at least on the hash key, wherein the FTAG value is associated with a multicast distribution tree in the overlay network; and

concatenating an overlay multicast group value with the FTAG value to provide a destination address.

9. The computer-implemented method of claim 8, further comprising:

encapsulating the multicast packet with the concatenated overlay multicast group value and the FTAG value; and

forwarding the encapsulated multicast packet to a network element located at a next-hop in the overlay network.

10. The computer-implemented method of claim 8, wherein the multicast packet is received by a virtual extensible local area network (VXLAN) tunnel end point (VTEP) in the overlay network.

11. The computer-implemented method of claim 8, wherein the hash operation is performed on at least one of an IP destination address or an IP source address in an IP header of the multicast packet, information in an layer 2 (L2) header, or information in the multicast packet indicating a UDP port number or a TCP port number.

12. The computer-implemented method of claim 8, wherein the FTAG value is associated with a multicast distribution tree selected from a plurality of multicast distribution trees in the overlay network.

13. The computer-implemented method of claim 8, wherein the overlay multicast group value comprises an overlay multicast group address.

14. The computer-implemented method of claim 13, wherein the FTAG value comprises a lower four bits of a header field including the concatenated overlay multicast group value and the FTAG value.

15. A non-transitory computer-readable medium including instructions stored therein that, when executed by at least one computing device, cause the computing device to perform operations comprising:

receiving, over a network interface, a multicast packet for distributing to a set of receivers in an overlay network;

performing a hash operation on at least a portion of the multicast packet to determine a hash key;

selecting a forwarding tag (FTAG) value based at least on the hash key, wherein the FTAG value is associated with a multicast distribution tree in the overlay network; and

concatenating an overlay multicast group value with the FTAG value to provide a destination address.

16. The non-transitory computer-readable medium of claim 15, wherein the computing device is further configured to perform operations comprising:

encapsulating the multicast packet with the concatenated overlay multicast group value and the FTAG value; and

forwarding the encapsulated multicast packet to a network element located at a next-hop in the overlay network.

17. The non-transitory computer-readable medium of claim 15, wherein the multicast packet is received by a virtual extensible local area network (VXLAN) tunnel end point (VTEP) in the overlay network.

18. The non-transitory computer-readable medium of claim 15, wherein the hash operation is performed on at least one of an IP destination address or an IP source address in an IP header of the multicast packet, information in an layer 2 (L2) header, or information in the multicast packet indicating a UDP port number or a TCP port number.

19. The non-transitory computer-readable medium of claim 15, wherein the FTAG value is associated with a multicast distribution tree selected from a plurality of multicast distribution trees in the overlay network.

20. The non-transitory computer-readable medium of claim 15, wherein the overlay multicast group value comprises an overlay multicast group address.