Method for implementing service chain, device, and system

Patent metadata

Field	Value
Publication number	US-10700891-B2
Application number	US-201715835603-A
Country	US
Kind code	B2
Filing date	Dec 8, 2017
Priority date	Jun 10, 2015
Publication date	Jun 30, 2020
Grant date	Jun 30, 2020

Abstract

A method of implementing a service chain in a service chain-enabled domain network includes: receiving, by an intermediate service node (SN), an extended first Border Gateway Protocol (BGP) packet from a downstream SN that is on a service chain path and immediately adjacent to the intermediate SN, the extended first BGP packet including a service chain path identifier identifying the service chain path and a first service chain path including a service chain path from an ingress SN to the intermediate SN, determining an upstream SN that is on the first service chain path and immediately adjacent to the intermediate SN, and sending an extended second BGP packet to the upstream SN, the extended second BGP packet including the service chain path identifier and a second service chain path including a service chain path from the ingress SN to the upstream SN.

First claim

What is claimed is:

1. A method of implementing a service chain in a service chain-enabled domain network, wherein service nodes (SNs) and a service chain path are configured to be deployed in the service chain-enabled domain network, the SNs comprise an ingress SN, an intermediate SN, and an egress SN, and the service chain path comprises a path from the ingress SN to the egress SN through the intermediate SN, the method comprising:
receiving, by the intermediate SN, an extended first Border Gateway Protocol (BGP) packet sent by a downstream SN that is on the service chain path and immediately adjacent to the intermediate SN, wherein the extended first BGP packet comprises a service chain path identifier and a first service chain path, the service chain path identifier identifies the service chain path, and the first service chain path comprises a service chain path from the ingress SN to the intermediate SN;
determining, by the intermediate SN, an upstream SN that is on the first service chain path and immediately adjacent to the intermediate SN; and
sending, by the intermediate SN, an extended second BGP packet to the upstream SN, wherein the extended second BGP packet comprises the service chain path identifier and a second service chain path, and the second service chain path comprises a service chain path from the ingress SN to the upstream SN;
wherein after the receiving, by the intermediate SN, the extended first BGP packet sent by the downstream SN, the method further comprises:
establishing, by the intermediate SN, a first tunnel from the intermediate SN to the downstream SN with the downstream SN, and linking the first tunnel to a second tunnel to form one tunnel according to the service chain path identifier, wherein the second tunnel is from the upstream SN to the intermediate SN and established by the upstream SN with the intermediate SN.

2. The method according to claim 1 , wherein the extended first BGP packet further comprises a tunnel type, the tunnel type being a label switched path (LSP) tunnel, and
wherein the establishing, by the intermediate SN, the first tunnel from the intermediate SN to the downstream SN with the downstream SN, and linking the first tunnel to the second tunnel to form one tunnel according to the service chain path identifier comprises:
obtaining, by the intermediate SN, a first label from the extended first BGP packet, wherein the first label is allocated by the downstream SN to the service chain path identifier, and establishing, by the intermediate SN, the first tunnel with the downstream SN, wherein the first tunnel is an LSP tunnel from the intermediate SN to the downstream SN;
allocating, by the intermediate SN, a second label to the service chain path identifier, and adding the second label to the extended second BGP packet, wherein the second label is used by the upstream SN to establish the second tunnel with the intermediate SN, and the second tunnel is an LSP tunnel from the upstream SN to the intermediate SN; and
associating, by the intermediate SN, the second label with the first label according to the service chain path identifier, and generating a label forwarding table to link the first tunnel to the second tunnel to form the one tunnel, wherein the second label is configured to be an incoming label and the first label is configured to be an outgoing label in the label forwarding table.

3. The method according to claim 1 , wherein the extended first BGP packet comprises a tunnel type, the tunnel type being a network virtualization over layer 3 (NVO3) tunnel, and
wherein the establishing, by the intermediate SN, the first tunnel from the intermediate SN to the downstream SN with the downstream SN, and linking the first tunnel to the second tunnel to form one tunnel according to the service chain path identifier comprises:
obtaining, by the intermediate SN, a first tunnel destination identifier from the extended first BGP packet, wherein the first tunnel destination identifier comprises an IP address of the downstream SN and a first local service chain path identifier allocated by the downstream SN to the service chain path, and establishing, by the intermediate SN, the first tunnel with the downstream SN, wherein the first tunnel is an NVO3 tunnel from the intermediate SN to the downstream SN;
allocating, by the intermediate SN, a second local service chain path identifier to the service chain path, generating a second tunnel destination identifier according to the second local service chain path identifier, and adding the second tunnel destination identifier to the extended second BGP packet, wherein the second tunnel destination identifier comprises an IP address of the intermediate SN and the second local service chain path identifier, the second tunnel destination identifier is used by the upstream SN to establish the second tunnel with the intermediate SN, and the second tunnel is an NVO3 tunnel from the upstream SN to the intermediate SN; and
associating, by the intermediate SN, the second tunnel destination identifier with the first tunnel destination identifier according to the service chain path identifier, and generating a forwarding information table to link the first tunnel to the second tunnel to form the one tunnel.

4. The method according to claim 3 , wherein the NVO3 tunnel is a virtual extensible local area network (VXLAN) tunnel or a network virtualization using generic routing encapsulation (NVGRE) tunnel, and
wherein the method further comprises:
receiving, by the intermediate SN, a service data packet of the service chain that is sent by the upstream SN, terminating a tunnel encapsulation header of the second tunnel in the service data packet, and reencapsulating a tunnel encapsulation header of the first tunnel, wherein a specific field of the tunnel encapsulation header of the first tunnel is filled with the first local service chain path identifier,
wherein, when the tunnel type is the VXLAN tunnel, the filled specific field is a VXLAN network identifier (VNI) field of a VXLAN header, and when the tunnel type is an NVGRE tunnel, the filled specific field is a virtual subnet identifier (VSI) field of an NVGRE header.

5. The method according to claim 3 , wherein the extended first BGP packet carries extended network layer reachability information (NLRI) including a length field, a tunnel destination identifier field, and a service chain policy field,
wherein the tunnel destination identifier field comprises at least a local service chain identifier field carrying the first local service chain path identifier and a destination IP address field carrying the IP address of the downstream SN, and
wherein the service chain policy field comprises a service chain path identifier field carrying the service chain path identifier and a service chain path sequence field carrying the first service chain path.

6. A service node (SN) in a service chain-enabled domain network, wherein SNs and a service chain path are configured to be deployed in the service chain-enabled domain network, the SNs comprises the SN as an intermediate SN, an ingress SN, and an egress SN, and the service chain path comprises a path from the ingress SN to the egress SN through the intermediate SN, the intermediate SN comprising:
a communications interface configured to receive an extended first Border Gateway Protocol (BGP) packet sent by a downstream SN that is on the service chain path and immediately adjacent to the intermediate SN, wherein the extended first BGP packet comprises a service chain path identifier and a first service chain path, the service chain path identifier identifies the service chain path, and the first service chain path comprises a service chain path from the ingress SN to the intermediate SN;
at least one processor; and

Assignees

• Huawei Tech Co Ltd

Inventors

• Hao Weiguo
• Liang Qiandeng
• Huang Shibi

Classifications

• H04L45/306 Primary

  Route determination based on the nature of the carried application · CPC title

• H04L47/2441

  relying on flow classification, e.g. using integrated services [IntServ] · CPC title

• H04L12/4641

  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 title

• H04L45/38

  Flow based routing · CPC title

• H04L12/4633 Primary

  Interconnection of networks using encapsulation techniques, e.g. tunneling · CPC title