Validating routing decisions

A method, comprising:

• receiving, by a processor, a routing intent indicative of a request for a graph within a communication network;
• determining, by the processor, a routing decision for the routing intent based on a network model of the communication network;
• generating, by the processor, a witness for the routing decision, wherein the witness comprises a set of one or more sub-graphs in the communication network;
• evaluating, by the processor, the witness for the routing decision based on the routing intent and based on the network model of the communication network;
• and
• determining, by the processor based on evaluation of the witness for the routing decision, whether the routing decision is valid for the routing intent.

An apparatus, comprising:

• a processor and a memory communicatively connected to the processor, the processor configured to:
• receive a set of intent-witness pairs indicative of a set of routing intents, having respective witnesses associated therewith, associated with respective routing decisions validated for a network based on a network model of the communication network;
• receive, based on a route selection process, a set of modified intent-witness pairs comprising ones of the intent-witness pairs for which the respective witness of the respective routing intent has changed to a respective new witness;
• update capacity information of the network model, based on the set of intent-witness pairs and the set of modified intent-witness pairs, to provide thereby an updated network model for the communication network;
• and
• verify the routing intents of the set of modified intent-witness pairs based on evaluation of the respective new witnesses of the respective routing intents in the set of modified intent-witness pairs based on the updated network model for the communication network.