Câu 156: 400-051: CCIE Collaboration Written

Refer to the exhibit. Which option describes how this Cisco IOS SIP gateway, with an analog phone attached to its FXS port, handles an incoming informational SIP 180 response message without SDP?

1. A. It will enable early media cut-through.
2. B. It will generate local ring back. — đáp án hiện tại
3. C. It will do nothing because the message is informational.
4. D. It will terminate the call because this is an unsupported message format.
5. E. It will take the FXS port offhook.