USE OF NETWORK INFORMATION BASE STRUCTURE TO ESTABLISH COMMUNICATION BETWEEN APPLICATIONS

Some embodiments provide a program for managing several switching elements. The program receives, at a network information base (NIB) data structure that stores data for managing the several switching elements, a request to notify a first application that uses the NIB when a set of data stored in the NIB is changed. The program changes, in response to an instruction from a second application, the set of data in the NIB. The program sends a notification to the first application of the change to the set of data in the NIB.