CDN Request Routing Loop Prevention via Provider ID Lists

The patent applies preliminary action by maintaining a list of higher CDN-provider-IDs at each CDN node before request routing occurs. This pre-established knowledge structure enables immediate loop detection when requests are redirected, avoiding the need for complex real-time analysis of multi-level CDN topologies. The list is prepared in advance during CDN interconnection setup, allowing the system to handle complex topologies without increasing operational complexity.

The patent uses the list of higher CDN-provider-IDs as an intermediary mechanism that simplifies loop detection. Instead of directly analyzing complex multi-level CDN relationships, each CDN node uses this intermediary list to quickly determine whether a redirect would create a loop. This intermediary structure mediates between the complex topology and the simple detection logic, resolving the contradiction between extendibility and detection complexity.

The patent applies dynamics by enabling CDNs to dynamically select from multiple candidate providers in the list based on real-time conditions such as load, availability, and performance metrics. Rather than a static single-candidate approach, the system adaptively chooses the most appropriate CDN from the list, maintaining simple routing logic while improving availability through dynamic selection among multiple options.

The patent uses parameter changes by varying the selection criteria from the CDN provider list based on current system state. When one CDN is unavailable or overloaded, the system changes parameters such as selecting the next available candidate from the list, thus maintaining simple routing decisions while ensuring content delivery availability through parameter-based adaptation.