Abstract: A system for assuring service of SIP sessions in an internet protocol (IP) network, includes a plurality of probes connected to a plurality of network operators at a plurality of locations in the network and generating a plurality of event streams, and a service assurance manager which performs pattern matching to determine if an event pattern in the plurality of event streams matches a pre-defined event pattern, updates network data including a network operator data model and network routing characteristics based on a result of the pattern matching, and performs a correction based on the updated network data, the correction including avoiding a problematic portion of the network by one of session steering, session routing and session throttling.