US Patent 9313129 Logical router processing by network controller

Some embodiments provide a network controller for managing a logical network implemented across several managed network elements. The logical network includes at least one logical router. The network controller includes an input interface for receiving configuration state for the logical router. The network controller includes a table mapping engine for generating data tuples for distribution to the managed network elements in order for the managed network elements to implement the logical router. The network controller includes a route processing engine for receiving a set of input routes from the table mapping engine based on the configuration state for the logical router, performing a recursive route traversal process to generate a set of output routes, and returning the set of output routes to the table mapping engine. The table mapping engine uses the set of output routes to generate the data tuples for distribution to the plurality of managed network elements.