Sell ZXUN XAGCF: Access Gateway Control Function

ZXUN xAGCF is deployed in PES (PSTN/ISDN Emulation Subsystem), provides P1 interface downwards, and accesses IMS core network via Mw interface upwards. ZXUN xAGCF serves as MGC (media gateway controller) to control media gateway entity (e.g., RG