Methods and systems for service distribution using data path state replication and intermediate device mapping

A method comprising:

• receiving a first packet that includes a source address in a source address field and includes a destination address in a destination address field;
• selecting a selected service node that is one of a plurality of service nodes in a circular replication chain that replicates service state information;
• routing the first packet to the selected service node;
• using, by the selected service node, the service state information to produce a first response packet that is responsive to the first packet;
• changing the service state information of the selected service node while producing the first response packet;
• producing a first sync packet that a downstream peer that is one of the service nodes can use to update the service state information of the downstream peer based on the change caused by producing the first response packet;
• sending the first sync packet to the downstream peer;
• transmitting, by the selected service node, the first response packet to a source at the source address after the selected service node receives the first sync packet from an upstream peer;
• using a second sync packet that is received from the upstream peer that is one of the service nodes to change the service state information of the selected service node;
• and
• sending the second sync packet to the downstream peer.

A system comprising:

• a circular replication chain that includes a plurality of service nodes;
• and
• a switch fabric configured to receive a plurality of packets and to distribute the packets among the service nodes,
• wherein the service nodes are configured to use a plurality of sync packets to perform chain replication of service state information within the circular replication chain,
• wherein the service nodes are configured to receive workload capsules that are received in packets that have a destination IP address indicating at least one of the service nodes,
• wherein the service nodes are configured to use the service state information to produce response packets that acknowledge the workload capsules,
• wherein the response packets are sent in response to the packets,
• wherein every one of the service nodes has an upstream peer and receives sync packets from the upstream peer,
• wherein every one of the service nodes has a downstream peer and sends sync packets to the downstream peer,
• wherein the sync packets include information that the downstream peer can use to update the service state information of the downstream peer based on a change to the service state information of the upstream peer that is caused by processing a packet,
• wherein receiving a sync packet that is a self originated sync packet indicates that all of the service nodes in the circular replication chain has received the sync packet, and
• wherein each one of the service nodes is configured to send one of the sync packets to the downstream peer when processing a one of the packets changes the service state information.