NetPiler: Reducing Network Configuration Complexity through Policy Classification

As a network evolves over time, multiple operators modify the network configuration, without fully considering what has been done previously. Similar policies are defined more than once, and policies that become obsolete after a transition are left in the configuration. As a result, the network configuration becomes complicated and disorganized, escalating maintenance costs and operator faults. We present a method called NetPiler that groups common policies by discovering a set of shared features and that uses the groupings instead of using each individual policy for the configuration. Such an approach removes redundancies and simplifies the configuration while preserving the intended behavior of the configuration. We apply NetPiler to the routing policy configurations from four different networks, and reduce more than 50% of BGP communities and the related commands. In addition, we show that the reduced community definitions are sufficient to satisfy the changes as the network evolves over almost two years.