Select the advantage of the Cisco ASA phone proxy feature:

A.
Enables advanced H.323 inspection services that support H.323 versions 1 along with Direct
Call Signaling (DCS) and Gatekeeper-Routed Call Signaling (GKRCS) to provide flexible security
integration in a variety of H.323-driven VoIP environments

B.
Enables inspection of the RTSP protocols that are used to control communications between the
client and server for streaming applications

C.
Allows telecommuters to connect their IP phones to the corporate IP telephony network
securely over the Internet, without the need to connect over a VPN tunnel

D.
Allows businesses to configure granular policies for SCCP traffic, such as enforcing only
registered phone calls to send traffic through the Cisco ASA security appliance and filtering to
message IDs to allow or disallow specific messages