A policy server and a charging server authorize and authenticate data traffic bypassing a mobile network. The policy server stores subscriber records, each containing one a mobile subscriber identifier corresponding to a communication device. The policy server receives a control session request from a gateway server in a fixed broadband network, including a broadband subscriber identifier and a first network address. Responsive to receiving the request, the policy server creates and stores a control session record including the broadband subscriber identifier and the first network address. The policy server receives an access session request from an application server in a multimedia network, including a mobile subscriber identifier and a second network address. The policy server determines whether the first network address matches the second network address; and when the determination is affirmative, updates the control session record to insert the mobile subscriber identifier.