Method, system and policy control and charging roles function (PCRF) for realizing backward quality-of-service (QoS) insurance and content charging

The invention relates to a method, a system and a policy control and charging roles function (PCRF) for realizing backward quality-of-service (QoS) insurance and content charging. The method comprises the steps of receiving a strategy and charging control request which is initialized by an application in response to service initiation of the application, wherein the strategy and charging control request carries a service identification and quintuple information which corresponds with the service identification; acquiring a corresponding PCC strategy according to the service identification; and transmitting a correspondence between the PCC strategy and the quintuple information to a policy control and charging enhancement function (PCEF), thereby realizing QoS insurance and content charging for different services. The method, a system and a policy control and charging roles function make the policy control and charging enhancement function (PCEF) correctly perceive different services.