Handling packet fragments in a distributed network service environment

A method for providing a network service, comprising:

• communicating a fragment criteria from a service manager to a forwarding agent that instructs the forwarding agent how to determine whether a received packet fragment at the forwarding agent matches the fragment criteria;
• receiving a matching packet fragment from the forwarding agent at a fragment service manager;
• positioning the matching packet fragment into a packet at the fragment service manager;
• in the event that the matching packet fragment completes the packet, determining from the completed packet a flow identifier specifying a flow;
• and
• communicating the completed packet to a selected one of a plurality of service managers that handles the flow specified in the flow identifier, wherein the fragment service manager compares the flow to a list of stored wildcard affinities communicated by one or more additional service managers.

A method for providing a network service, further comprising:

• communicating a fragment criteria from a service manager to a forwarding agent that instructs the forwarding agent how to determine whether a received packet fragment at the forwarding agent matches the fragment criteria;
• receiving a matching packet fragment from the forwarding agent at a fragment service manager;
• positioning the matching packet fragment into a packet at the fragment service manager;
• in the event that the matching packet fragment completes the packet, determining from the completed packet a flow identifier specifying a flow;
• and
• communicating the completed packet to a selected service manager that handles the flow specified in the flow identifier, wherein the fragment service manager compares the flow to a list of stored fixed affinities sent by one or more additional service managers.

A method for providing a network service, further comprising:

• communicating a fragment criteria from a service manager to a forwarding agent that instructs the forwarding agent how to determine whether a received packet fragment at the forwarding agent matches the fragment criteria;
• receiving a matching packet fragment from the forwarding agent at a fragment service manager;
• positioning the matching packet fragment into a packet at the fragment service manager;
• in the event that the matching packet fragment completes the packet, determining from the completed packet a flow identifier specifying a flow;
• and
• communicating the completed packet to a selected one of a plurality of service managers that handles the flow specified in the flow identifier, wherein the fragment service manager receives affinities specifying sets of flows from an additional service manager, and wherein the fragment service manager derives the fragment criteria from the sets of flows so that the fragment service manager assembles fragments for packets that are candidates to match the affinities.

A method for providing a network service, comprising:

• providing a forwarding agent in a network device, wherein the forwarding agent stores one or more fragment criteria received from a fragment service manager;
• receiving a packet fragment at the forwarding agent;
• determining whether the fragment matches the fragment criteria;
• and
• forwarding the fragment from the forwarding agent to the fragment service manager in the event that the fragment matches the fragment criteria so that the fragment may be assembled into a packet at the fragment service manager and in the event that the fragment completes the packet, a flow identifier specifying a flow is determined from the completed packet and the completed packet may be communicated to a selected one of a plurality of service managers that handles the flow specified in the flow identifier.

A forwarding agent for handling packet fragments, comprising:

• a fragment service manager receiving interface for receiving instructions from a fragment service manager specifying fragment criteria for packet fragments that are to be communicated to the fragment service manager;
• a fragment service manager sending interface for communicating packet fragments to the fragment service manager;
• a network packet receiving interface for receiving internet protocol (IP) packet fragments from a network;
• and
• a processor for determining whether packet fragments received on the network packet receiving interface match the fragment criteria, wherein the fragment criteria reflect one or more affinities operable to specify a source internet protocol (IP) address and a destination IP address.

A fragment service manager for handling packet fragments, comprising:

• a fragment criteria sending interface operable to send fragment criteria to a plurality of forwarding agents, the fragment criteria specifying fragments that are to be sent to the fragment service manager;
• a fragment receiving interface operable to receive fragments matching the fragment criteria from the plurality of forwarding agents;
• a fragment processor operable to assemble the received fragments into packets;
• and
• a packet processor operable to determine a designated service manager for handling the assembled packets.

A computer readable medium having code for handling packet fragments, the code operable to:

• store one or more fragment criteria received from a fragment service manager on a forwarding agent;
• receive a packet fragment at the forwarding agent;
• determine whether the fragment matches the fragment criteria;
• forward the packet fragment from the forwarding agent to the fragment service manager in the event that the packet fragment matches the fragment criteria;
• position the packet fragment into a packet at the fragment service manager;
• in the event that the fragment completes the packet, determine from the completed packet a flow identifier specifying a flow;
• and
• communicate the completed packet to a service manager that handles the flow specified in the flow identifier.

A computer readable medium having code for handling packet fragments, the code operable to:

• send fragment criteria to a plurality of forwarding agents, the fragment criteria specifying fragments that are to be sent to a fragment service manager;
• receive fragments matching the fragment criteria from the plurality of forwarding agents;
• assemble the received fragments into packets;
• and
• determine a designated service manager for handling the assembled packets.

A system for providing a network service, comprising:

• means for storing one or more fragment criteria received from a fragment service manager;
• means for receiving a packet fragment;
• means for determining whether the packet fragment matches the fragment criteria;
• means for forwarding the packet fragment from a forwarding agent to the fragment service manager in the event that the fragment matches the fragment criteria;
• means for assembling the fragment into a packet;
• means determining a flow identifier specifying a flow from a completed packet;
• and
• means for communicating the completed packet to a service manager that handles the flow specified in the flow identifier.