Service Function Chaining Congestion Tracking

Abstract

A computer-implemented method tracks congestion in a service function chain. The method includes receiving a packet at a service function forwarding node of the service function chain, the packet having an information packet, a transport header, and a network service header, forwarding the packet to a service function in accordance with the network service header, detecting congestion, and updating a congestion field in the network service header to indicate congestion was encountered in the service function chain.

What is claimed is: 
     
         1 . A method for tracking and controlling congestion in a service function chain by a service function forwarding node, comprising:
 receiving a packet, wherein the packet comprises a congestion field used to indicate a congestion state in a service function chain;   obtaining congestion information based on the congestion field; and   transmitting the congestion information to a first node for congestion control.   
     
     
         2 . The method of  claim 1 , wherein the controlling congestion comprises limiting a flow to which the packet belong. 
     
     
         3 . The method of  claim 2 , wherein the limiting the flow comprises sending a message to a source of the flow based on the congestion information to limit the flow. 
     
     
         4 . The method of  claim 1 , wherein controlling the congestion comprises re-directing a path of the flow to which the packet belongs. 
     
     
         5 . The method of  claim 4 , wherein the re-directing comprises selecting a path with less congestion for a next packet of the flow. 
     
     
         6 . The method of  claim 5 , wherein the selecting the path comprises: adding a service path identifier corresponding to the path with less congestion to the next packet of the flow. 
     
     
         7 . The method of  claim 1 , wherein the congestion field comprises two bits in a network service header of the packet. 
     
     
         8 . The method of  claim 7 , wherein at least one non-zero bit in the congestion field indicates that congestion tracking of the packet is activated. 
     
     
         9 . The method of  claim 1 , wherein a value of the congestion field is used to indicate a congestion degree. 
     
     
         10 . The method of  claim 9 , wherein a higher value of the congestion field indicates a more severe congestion degree. 
     
     
         11 . The method of  claim 1 , wherein the packet comprises a service path identifier, and the service path identifier is used to identify a service path corresponding to the service function chain. 
     
     
         12 . The method of  claim 1 , wherein the packet comprises a network service header added by the first node comprises the congestion field. 
     
     
         13 . The method of  claim 1 , wherein the first node is a classifier, a first service function forwarding node of the service function chain, or an ingress node of a service function chain domain. 
     
     
         14 . The method of  claim 7 , wherein one non-zero bit and one zero bit in the congestion field indicate supporting congestion tracking of the packet. 
     
     
         15 . The method of  claim 7 , wherein two non-zero bits in the congestion field indicate a congestion in the service function chain 
     
     
         16 . A service function forwarding node for tracking and controlling congestion, comprising:
 a processor; and   a non-transitory computer-readable storage medium coupled to the processor and storing programming instructions for execution by the processor, the programming instructions cause the service function forwarding node to:   receive a packet, wherein the packet comprises a congestion field used to indicate a congestion state in a service function chain;   obtain congestion information based on the congestion field; and   transmit the congestion information to a first node for congestion control.   
     
     
         17 . The node of  claim 16 , wherein the congestion control comprises limiting a flow to which the packet belong. 
     
     
         18 . The node of  claim 17 , wherein the limiting the flow to which the packet belong comprises sending a message to a source of the flow based on the congestion information to limit the flow. 
     
     
         19 . The node of  claim 16 , wherein the congestion control comprises re-directing a path of the flow to which the packet belong. 
     
     
         20 . The node of  claim 19 , wherein the re-directing the path of the flow to which the packet belong comprises selecting a path with less congestion for a next packet of the flow. 
     
     
         21 . The node of  claim 20 , wherein the selecting a path with less congestion for a next packet of the flow comprises: adding a service path identifier corresponding to the path with less congestion to the next packet of the flow. 
     
     
         22 . The node of  claim 16  wherein the congestion field comprises two bits in a network service header of the packet. 
     
     
         23 . The node of  claim 22 , wherein at least one non-zero bit in the congestion field indicates that congestion tracking of the packet is activated. 
     
     
         24 . The node of  claim 16 , wherein a value of the congestion field is used to indicate a congestion degree. 
     
     
         25 . The node of  claim 24 , wherein a higher value of the congestion field indicates a more severe congestion degree. 
     
     
         26 . The node of  claim 16  wherein the packet comprises a service path identifier, and the service path identifier is used to identify a service path corresponding to the service function chain. 
     
     
         27 . The node of  claim 16 , wherein the packet comprises a network service header added by the first node comprises the congestion field. 
     
     
         28 . The node of  claim 16 , wherein the first node is a classifier, a first service function forwarding node of the service function chain, or an ingress node of a service function chain domain. 
     
     
         29 . The node of  claim 22 , wherein one non-zero bit and one zero bit in the congestion field indicate supporting congestion tracking of the packet. 
     
     
         30 . The node of  claim 22 , wherein two non-zero bits in the congestion field indicate a congestion in the service function chain 
     
     
         31 . A method for tracking congestion in a service function chain by a first node, comprising:
 sending a packet, wherein the packet comprises a congestion field used to indicate a congestion state in a service function chain; and   receiving congestion information fed back by a service function forwarding node, for congestion control.   
     
     
         32 . The method of  claim 31 , wherein the congestion control comprises limiting a flow to which the packet belong. 
     
     
         33 . The method of  claim 32 , wherein the limiting the flow to which the packet belong comprises sending a message to a source of the flow based on the congestion information to limit the flow. 
     
     
         34 . The method of  claim 31 , wherein the congestion control comprises re-directing a path of the flow to which the packet belong. 
     
     
         35 . The method of  claim 34 , wherein the re-directing the path of the flow to which the packet belong comprises selecting a path with less congestion for a next packet of the flow. 
     
     
         36 . The method of  claim 35 , wherein the selecting a path with less congestion for a next packet of the flow comprises: adding a service path identifier corresponding to the path with less congestion to the next packet of the flow. 
     
     
         37 . The method of  claim 31 , wherein the congestion field comprises two bits in a network service header of the packet. 
     
     
         38 . The method of  claim 37 , wherein at least one non-zero bit in the congestion field indicates that congestion tracking of the packet is activated. 
     
     
         39 . The method of  claim 31 , wherein a value of the congestion field is used to indicate a congestion degree. 
     
     
         40 . The method of  claim 39 , wherein a higher value of the congestion field indicates a more severe congestion degree. 
     
     
         41 . The method of  claim 31 , wherein the first node is a classifier, a first service function forwarding node of the service function chain, or an ingress node of a service function chain domain. 
     
     
         42 . The method of  claim 37 , wherein one non-zero bit and one zero bit in the congestion field indicate supporting congestion tracking of the packet. 
     
     
         43 . The method of  claim 37 , wherein two non-zero bits in the congestion field indicate a congestion in the service function chain 
     
     
         44 . A first node, comprising:
 a processor; and   a non-transitory computer-readable storage medium coupled to the processor and storing programming instructions for execution by the processor, the programming instructions cause the first node to:   send a packet, wherein the packet comprises a congestion field used to indicate a congestion state in a service function chain; and   receive congestion information fed back by a service function forwarding node, for congestion control.   
     
     
         45 . The first node of  claim 44 , wherein the congestion control comprises limiting a flow to which the packet belong. 
     
     
         46 . The first node of  claim 45 , wherein the limiting the flow to which the packet belong comprises sending a message to a source of the flow based on the congestion information to limit the flow. 
     
     
         47 . The first node of  claim 44 , wherein the congestion control comprises re-directing a path of the flow to which the packet belong. 
     
     
         48 . The first node of  claim 47 , wherein the re-directing the path of the flow to which the packet belong comprises selecting a path with less congestion for a next packet of the flow. 
     
     
         49 . The first node of  claim 48 , wherein the selecting a path with less congestion for a next packet of the flow comprises: adding a service path identifier corresponding to the path with less congestion to the next packet of the flow. 
     
     
         50 . The first node of  claim 44 , wherein the congestion field comprises two bits in a network service header of the packet. 
     
     
         51 . The first node of  claim 50 , wherein at least one non-zero bit in the congestion field indicates that congestion tracking of the packet is activated. 
     
     
         52 . The first node of  claim 44 , wherein a value of the congestion field is used to indicate a congestion degree. 
     
     
         53 . The first node of  claim 52 , wherein a higher value of the congestion field indicates a more severe congestion degree. 
     
     
         54 . The first node of  claim 44 , wherein the first node is a classifier, a first service function forwarding node of the service function chain, or an ingress node of a service function chain domain. 
     
     
         55 . The first node of  claim 50 , wherein one non-zero bit and one zero bit in the congestion field indicate supporting congestion tracking of the packet. 
     
     
         56 . The first node of  claim 50 , wherein two non-zero bits in the congestion field indicate a congestion in the service function chain 
     
     
         57 . A system, comprising:
 a first node, configured to send a packet, wherein the packet comprises a congestion field used to indicate a congestion state in a service function chain; and   a service function forwarding node, configured to:   receive the packet comprising the congestion field;   obtain congestion information based on the congestion field; and   transmit the congestion information to the device applied to the first node for congestion control; and   the device applied to the first node is configured to receive the congestion information fed back by the device applied to the service function forwarding node for congestion control.