Encoding control plane information in transport protocol source port field and applications thereof in network virtualization

Patent metadata

Field	Value
Publication number	US-9577927-B2
Application number	US-201414320453-A
Country	US
Kind code	B2
Filing date	Jun 30, 2014
Priority date	Jun 30, 2014
Publication date	Feb 21, 2017
Grant date	Feb 21, 2017

Abstract

A novel method that uses the source port field in the transport or connection layer (L4) header to encode control plane information is provided. Specifically, the method encodes control plane information in UDP or TCP source port field of data plane tunnels in an overlay network such as VXLAN. Network virtualization is implemented by a network controller over an overlay network on the physical fabric. The network controller provides a mapping table to the data plane hosts for mapping the encoded bits in the source port field to semantically richer information. The data plane hosts in turn uses the encoded source bits and the mapping table to infer this semantically richer information. This semantically richer information is used to allow receivers of proxied traffic to learn the address of the original sender. The semantically richer information can also be used to enable ECMP for the transmitted packets.

First claim

What is claimed is:

1. A method for forwarding packets in an overlay logical network, each packet comprising a L4 source port field, a L4 destination port field, a L3 source address field, and a L3 destination address field, the method comprising:
receiving a mapping table for encoding L3 IP addresses into identifiers to be stored in the L4 source port fields of the packets;
receiving, at a first tunnel endpoint, a first packet from a second tunnel endpoint in an overlay logical network, the first packet storing an IP address of the second tunnel endpoint in the L3 source address field of the first packet and an identifier of an original sender in the L4 source port field of the first packet, the original sender being different than the second tunnel endpoint;
identifying the original sender of the first packet by using the received mapping table to extract the IP address of the original sender from the identifier stored in the L4 source port field of the first packet; and
transmitting a second packet to the identified original sender of the first packet by using the decoded IP address of the original sender.

2. The method of claim 1 , wherein the overlay logical network is a virtual extensible local area network (“VXLAN”).

3. The method of claim 1 , wherein the first packet is a multicast packet.

4. The method of claim 1 , wherein the first packet is transmitted by a multicast proxy tunnel endpoint.

5. The method of claim 4 , wherein the L3 source address field of the first packet carries an IP address of the multicast proxy tunnel endpoint.

6. The method of claim 4 , wherein the L4 source port field of the packet further comprises a bit for enabling multicast transmission by the multicast proxy tunnel endpoint.

7. The method of claim 1 further comprising receiving a mapping table for mapping bits in the L4 source port field to an address of a tunnel endpoint.

8. The method of claim 1 , wherein the computing device is running virtualization software for hosting at least one virtual machine.

9. A method for forwarding packets in an overlay logical network, each packet comprising a L4 source port field, a L4 destination port field, a L3 source address field, and a L3 destination address field, the method comprising:
receiving a mapping table for encoding L3 IP addresses into identifiers to be stored in the L4 source port fields of the packets;
providing the mapping table to a first tunnel endpoint and a second tunnel endpoint in the overlay logical network,
wherein the first tunnel endpoint uses the mapping table to encode an IP address of the first tunnel endpoint into a particular identifier and stores the encoded particular identifier into the L4 source port field of a first packet; and
wherein the second tunnel endpoint uses the mapping table to decode the IP address of the first tunnel endpoint from the particular identifier stored in the L4 source port field of a second packet, wherein the second packet is a replicated packet based on the first packet that is received from a third tunnel endpoint.

10. The method of claim 9 , wherein the overlay logical network comprises a plurality of tunnel endpoints that includes the first, second, and third tunnel endpoints, wherein the mapping table comprises entries that correspond to an address of each tunnel endpoint of the logical network.

11. The method of claim 10 further comprising providing the mapping table to each tunnel endpoint of the logical network.

12. The method of claim 9 , wherein the third tunnel endpoint is a proxy tunnel endpoint that fills the L3 source address field of the second packet with the address of the third tunnel end point.

13. The method of claim 12 , wherein the third tunnel endpoint is a multicast proxy tunnel endpoint that replicates packets from other tunnel endpoints, wherein the second packet is a replicated packet.

14. The method of claim 12 , wherein the third tunnel endpoint enables multicast replication based on a flag bit encoded in the L4 source port field of a third packet received by the third tunnel endpoint.

15. The method of claim 9 , wherein a tunnel endpoint is operated by virtualization software running on a computing device, wherein the virtualization software allows the computing device to host at least one virtual machine.

16. The method of claim 9 , wherein the overlay logical network is a virtual extensible local area network (“VXLAN”).

Assignees

• Nicira Inc

Inventors

• Hira Mukesh
• Tessmer Alexander
• Chanda Anupam

Classifications

• H04L45/745

  Address table lookup; Address filtering · CPC title

• H04L45/64 Primary

  using an overlay routing layer · CPC title

• H04L49/354

  for supporting virtual local area networks [VLAN] · CPC title

• H04L45/16

  Multipoint routing · CPC title

• H04L69/22

  Parsing or analysis of headers · CPC title