Network service header (nsh) relaying of serviceability of a service function

Abstract

At a service function node configured to perform at least one service function on a data flow that follows a service function path, degradation in performing the service function is detected. The service function node generates a status indicator for the degradation in performing the service function and inserts the status indicator into a peer detection packet. The peer detection packet encapsulates an inner packet with a header that indicates the service function path. The service function node forwards the peer detection packet to a neighboring service function node along the service function path.

What is claimed is: 
     
         1 . A method comprising:
 at a computing device configured to perform at least one service function on a data flow that follows a service function path, detecting a degradation in performing the service function;   generating a status indicator for the degradation in performing the service function;   inserting the status indicator into a peer detection packet, the peer detection packet encapsulating an inner packet with a header that indicates the service function path; and   forwarding the peer detection packet to a neighboring service function device along the service function path.   
     
     
         2 . The method of  claim 1 , wherein the status indicator is inserted as metadata in a network service header of the inner packet of the peer detection packet. 
     
     
         3 . The method of  claim 1 , further comprising inserting service function statistical information into the network service header, wherein the service function statistical information describes the performance level of the computing device in performing the at least one service function. 
     
     
         4 . The method of  claim 1 , wherein the status indicator indicates one or more of a success status, a redirection status, or a server error status. 
     
     
         5 . The method of  claim 1 , further comprising:
 receiving a peer detection request packet from the neighboring service function device; and   replying to the peer detection request packet with the peer detection packet including the status code.   
     
     
         6 . The method of  claim 1 , wherein the peer detection packet comprises a Generic Routing Encapsulation (GRE) keepalive notification packet, a GRE response packet, an Internet Security Association and Key Management Protocol (ISAKMP) R-U-THERE message, or an ISAKMP R-U-THERE-ACK message. 
     
     
         7 . An apparatus comprising:
 a network interface unit configured to communicate with a plurality of service function devices in a service function path; and   a processor configured to:
 perform at least one service function on a data flow that follows the service function path; 
 detect a degradation in performing the service function; 
 generate a status indicator for the degradation in performing the service function; 
 insert the status indicator into a peer detection packet, the peer detection packet encapsulating an inner packet with a header that indicates the service function path; and 
 cause the network interface unit to forward the peer detection packet to a neighboring service function device along the service function path. 
   
     
     
         8 . The apparatus of  claim 7 , wherein the processor is configured to insert the status indicator as metadata in a network service header of the inner packet of the peer detection packet. 
     
     
         9 . The apparatus of  claim 7 , wherein the status indicator indicates one or more of a success status, a redirection status, or a server error status. 
     
     
         10 . The apparatus of  claim 7 , wherein the processor is further configured to:
 receive a peer detection request packet, via the network interface unit, from the neighboring service function device; and   cause the network interface unit to reply to the peer detection request packet with the peer detection packet including the status indicator.   
     
     
         11 . The apparatus of  claim 7 , wherein the peer detection packet comprises a Generic Routing Encapsulation (GRE) keepalive notification packet, a GRE response packet, an Internet Security Association and Key Management Protocol (ISAKMP) R-U-THERE message, or an ISAKMP R-U-THERE-ACK message. 
     
     
         12 . A method comprising:
 receiving a peer detection packet from a service function device in a service function path, the peer detection packet comprising an inner packet with a header;   detecting an status indicator in the header, the status indicator indicating a degradation in performing a service function at the service function device; and   adjusting the service function path to compensate for the degradation in performing the service function at the service function device.   
     
     
         13 . The method of  claim 12 , wherein the status indicator is detected as metadata in a network service header. 
     
     
         14 . The method of  claim 12 , wherein the status indicator indicates one or more of a success status, a redirection status, or a server error status. 
     
     
         15 . The method of  claim 14 , further comprising:
 responsive to the status indicator indicating a redirection status, adjusting the service function path by redirecting future data flows to an alternative data center as indicated in the redirection status; and   responsive to the status indicator indicating a server error status, adjusting the service function path by redirecting the future data flows to a predetermined secondary data center.   
     
     
         16 . The method of  claim 12 , wherein adjusting the service function path comprises sending a new peer detection packet to a previous device in the service function path. 
     
     
         17 . The method of  claim 16 , wherein the previous device is a previous service function device, a service function classifier device, or service function forwarder device. 
     
     
         18 . The method of  claim 12 , wherein adjusting the service function path comprises classifying a data flow into a new service function path that avoids the service function device. 
     
     
         19 . The method of  claim 12 , wherein adjusting the service function path comprises providing the service function from a different service function device. 
     
     
         20 . The method of  claim 19 , further comprising determining the different service function device based on service function statistical information in the header.