Patent ID: 9686709
Date: 2017-06-20
CPC Classifications: H04L,H04W

Claim:
1. A method for guaranteeing quality of service (QoS) of a communication service in a network address translation (NAT) scenario, wherein the method is applicable to a proxy call session control function (P-CSCF) network element connected to an access border gateway function (A-BGF) network element and a policy and charging rules function (PCRF) network element, and the method comprises: receiving calling party Session Description Protocol (SDP) information sent by a user equipment so that the A-BGF network element generates proxy SDP information according to the calling party SDP information; replacing the calling party SDP information with the proxy SDP information to establish a connection between the user equipment and a called party that is different from the A-BGF network element, wherein the calling party SDP information comprises a first IP address and a first port of the user equipment, and the proxy SDP information comprises a second IP address and a second port of the A-BGF network element; after the connection between the user equipment and the called party is successfully established, instructing the PCRF network element to perform QoS resource reservation, wherein source address information required for performing the QoS resource reservation comprises the first IP address and the first port, and destination address information required for performing the QoS resource reservation comprises the second IP address and the second port; receiving a third IP address and a third port of the user equipment, where the third IP address and the third port are a result of NAT translation and acquired by the A-BGF network element from a media stream sent by the user equipment; and instructing the PCRF network element to update the source address information required for performing the QoS resource reservation to the third IP address and the third port, so that the PCRF network element performs the QoS resource reservation according to the updated source address information.