Various exemplary embodiments relate to a method and related network node and machine-readable storage medium relating to the receipt, association, and synchronization of a plurality of messages from diverse sources. Various embodiments relate to a Policy Charging and Rules Node (PCRN) receiving related messages from at least two sources and acquiring a lock associated with the received message's session binding identifier (SBI). The PCRN may use the lock to prioritize the processing of the related requests that share a common SBI. Various embodiments relate to the PCRN rejecting subsequent related requests unless the subsequent request is of a higher priority. Various other embodiments relate to the PCRN waiting for the receipt of the subsequent request before fully processing the first request.