Packet sending method, network node, and system

Abstract

A controller obtains a forwarding latency requirement of a service flow and a destination address of the service flow, and determines a forwarding path that meets the forwarding latency requirement. The controller determines that an ingress node forwards a first cycle time number of a packet and an intermediate node forwards a second cycle time number of the packet, and separately determines a corresponding adjacent segment identifier. A label stack generated by the controller includes the adjacent segment identifier and the adjacent segment identifier. The controller sends the label stack to the ingress node, to trigger the ingress node to forward the packet within a period of time corresponding to the first cycle time number. The controller determines the forwarding path based on the forwarding latency requirement of the service flow, and generates a label stack corresponding to a forwarding time point.

1 . A controller comprising:
 one or more memories configured to store instructions; and   one or more processors coupled to the one or more memories and configured to execute the instructions to cause the controller to:   determine a forwarding path for forwarding a service flow, wherein the forwarding path passes through a first network device and a second network device, the first network device is an ingress node of the forwarding path, and the second network device is an intermediate node of the forwarding path;   generate a segment identifier (SID) list corresponding to the forwarding path, wherein the SID list comprises a first SID and a second SID, the first SID corresponds to a first cycle number for sending a packet by the first network device, the second SID corresponds to a second cycle number for sending the packet by the second network device, and the packet is a packet in the service flow; and   send the SID list to the first network device, wherein the SID list is used to indicate to the first network device to forward the packet.   
     
     
         2 . The controller according to  claim 1 , wherein the first cycle number for sending the packet by the first network device corresponds to a first time for sending the packet by the first network device, the second cycle number for sending the packet by the second network device corresponds to a second time for sending the packet by the second network device. 
     
     
         3 . The controller according to  claim 1 , wherein the one or more processors are further configured to execute the instructions to cause the network device to:
 obtain a first node latency of the first network device and a second node latency of the second network device, wherein each of the first and second node latencies comprises a packet processing latency and a packet sending latency; and   obtain a link latency of a link on the forwarding path.   
     
     
         4 . The controller according to  claim 2 , wherein the one or more processors are further configured to execute the instructions to cause the network device to:
 obtain a first node latency of the first network device and a second node latency of the second network device, wherein each of the first and second node latencies comprises a packet processing latency and a packet sending latency; and   obtain a link latency of a link on the forwarding path.   
     
     
         5 . The controller according to  claim 3 , wherein a sum of the first node latency, the second node latency, and a link latency of the link on the forwarding path falls within a range of the forwarding latency requirement of the service flow. 
     
     
         6 . The controller according to  claim 4 , wherein a sum of the first node latency, the second node latency, and a link latency of the link on the forwarding path falls within a range of the forwarding latency requirement of the service flow. 
     
     
         7 . The controller according to  claim 1 , wherein the first SID and the second SID are MPLS labels. 
     
     
         8 . A first network device comprising:
 one or more memories configured to store instructions; and   one or more processors coupled to the one or more memories and configured to execute the instructions to cause the first network device to:   obtain a segment identifier (SID) list corresponding to a forwarding path for forwarding a packet, wherein the SID list comprises a second SID of a second network device, the first network device is an ingress node of the forwarding path, the second network device is an intermediate node of the forwarding path;   encapsulate the SID list in the packet; and   send the packet encapsulating the SID list to the second network device, wherein the second SID indicates a second cycle number for sending the packet by the second network device.   
     
     
         9 . The network device according to  claim 8 , wherein the second SID is a MPLS label. 
     
     
         10 . A first network device comprising:
 one or more memories configured to store instructions; and   one or more processors coupled to the one or more memories and configured to execute the instructions to cause the first network device to:   receive a packet sent by a second network device comprising a segment identifier (SID) list comprising a SID of the first network device;   determine a SID of the first network device that indicates a cycle number for sending the packet by the first network device; and   send the packet at a time corresponding to the cycle number.   
     
     
         11 . The network device according to  claim 10 , wherein the SID of the first network device corresponds to an interface of the first network device. 
     
     
         12 . The network device according to  claim 11 , wherein the one or more processors are further configured to execute the instructions to cause the network device to:
 add the packet to a queue corresponding to the cycle number, and send the packet via the interface corresponding to the SID of the first network device.   
     
     
         13 . The network device according to  claim 12 , wherein the second SID of the first network device is an adjacency SID.