According to one aspect of the present disclosure a system identifies a service level agreement between an originator of a network flow, and service level objectives associated with the agreement. The system generates and inserts one or more packet contracts into one or more packets in a data flow, with each packet contract specifying instructions that nodes that process the packet to generate accounting data, enabling measurement of the service level objectives, which is stored with the packet. Packet contract generation occurs by retrieving one or more packet contract templates associated with the service level agreement and generates an agreement based on the template. The accounting data can be carried with the packet to an egress node which can use the accounting data to determine whether the customer service levels are being met.