Utilizing the invention method can implement WAC between PSTN/PLMN user of the different physical network and NGN user without altering soft/hardware of the existing network switch.

• 采用本发明的方法能够在不需要对现网交换机作软硬件改动的情况下，在不同物理网络的PSTN/PLMN用户和NGN用户间实现WAC。