Network reachability impact analysis

A method of network reachability impact analysis, the method comprising:

• receiving, at data processing hardware, a stream of consecutive network configuration snapshots for a network;
• determining whether a first data plane model protocol of a first network configuration snapshot of the network from the stream of consecutive network configuration snapshots for the network is the same as a second data plane model protocol of a second network configuration snapshot of the network from the stream of consecutive network configuration snapshots for the network, the second network configuration snapshot of the network consecutive with the first network configuration snapshot in the stream of consecutive network configuration snapshots for the network;
• when the first data plane model protocol and the second data plane model protocol are the same, determining whether the second data plane model protocol of the second network configuration snapshot of the network is the same as a third data plane model protocol of a third network configuration snapshot of the network from the stream of consecutive network configuration snapshots for the network, the third network configuration snapshot of the network consecutive with the second network configuration snapshot in the stream of consecutive network configuration snapshots for the network;
• when the first data plane model protocol and the second data plane model protocol are not the same:
• selecting, by the data processing hardware, the first network configuration snapshot of the network and the second network configuration snapshot of the network;
• generating, by the data processing hardware, a first reachability graph representing packet reachability of the network for the first network configuration snapshot;
• generating, by the data processing hardware, a second reachability graph representing packet reachability of the network for the second network configuration snapshot;
• computing, by the data processing hardware, a reachability differentiation graph identifying a net change to reachability from the first reachability graph to the second reachability graph;
• and
• generating, by the data processing hardware, a reachability differentiation report including a human-interpretable output of the net change to reachability.