VPN Hub Resource Allocation via Priority Messages

The patent applies local quality by assigning different priority levels to different branch devices based on their criticality. The hub device maintains a priority table that associates each branch with a specific priority value, enabling differentiated resource allocation. Critical branches receive higher priority for CPU resources during tunnel re-establishment, while less critical branches receive lower priority, thus improving resource management efficiency without requiring complete system redesign.

The patent implements preliminary action by having branch devices include their priority information in the initial IKE connection establishment messages (such as IKE_SA_INIT or IKE_AUTH). The hub device receives and stores these priorities in advance in a priority table before any outage occurs. This pre-configured priority information is then automatically used during tunnel re-establishment after outages, ensuring service reliability for critical branches without requiring complex real-time priority negotiation or additional protocol complexity during critical events.

The patent applies periodic action by implementing a rate-limiting mechanism that controls the timing and frequency of tunnel re-establishment attempts based on branch priority. Critical branches are permitted to re-establish tunnels with higher frequency and lower delay, while less critical branches experience rate-limiting that spreads their re-establishment attempts over time. This priority-based rate limiting prevents CPU overload during outages while maintaining automatic failover capability, as all branches ultimately recover but at different rates determined by their priority levels.