Tunnel Packet Routing Using Fixed Header Values for Flow Consistency

The patent applies preliminary action by extracting flow identification information from packet headers before distribution decisions are made. The system pre-processes packets to identify their flow membership using fixed header fields, then uses this pre-established flow context to make consistent downstream destination selections. This ensures all packets from the same flow are routed to the same destination while still enabling parallel processing across multiple destinations for different flows.

The patent applies parameter changes by switching from using source IP address (which changes in tunneling scenarios) to using fixed header fields that remain constant throughout the tunneling process. Specifically, the system extracts routing decision parameters from fields like destination IP address, destination port, or protocol type that do not change when packets traverse tunnels. This parameter substitution maintains routing simplicity while ensuring consistent routing decisions regardless of source IP address changes.

The patent applies segmentation by separating the packet handling process into two distinct phases: flow identification phase and destination selection phase. In the first phase, packets are segmented by flow using fixed header fields to ensure consistency. In the second phase, within each flow group, the system introduces randomness for downstream destination selection to maintain load-balancing efficiency. This segmentation allows the system to simultaneously achieve flow consistency and load-balancing randomness by applying different strategies to different aspects of packet processing.