Which parameter in an NTFY message is used by a Cisco IOS MGCP gateway to inform a Cisco Unified CM that an analog endpoint has gone off-hook?
Click on the arrows to vote for the correct answerA. B. C. D. E.
The correct answer is D. Observed Events.
In the context of the MGCP (Media Gateway Control Protocol), an NTFY message (Notify) is used by a Cisco IOS MGCP gateway to inform a Cisco Unified CM (CallManager) of a change in the state of a particular device or endpoint connected to the gateway.
When an analog endpoint, such as an analog phone or fax machine, goes off-hook (i.e., lifted up to initiate a call), the MGCP gateway sends an NTFY message to the Cisco Unified CM to inform it of the change in state. The NTFY message contains information about the observed events that triggered the notification.
The Observed Events parameter in the NTFY message specifies the particular event or events that were observed by the MGCP gateway, such as off-hook, on-hook, dialing, or ringing. This information helps the Cisco Unified CM to accurately track the status of the endpoint and to initiate the appropriate call routing and processing procedures.
In contrast, the Detect Events parameter is used in the MGCP endpoint configuration to specify the events that the endpoint is capable of detecting, while the Event States parameter is used to specify the possible states or transitions of an endpoint based on the observed events. The Connection Mode parameter is used to specify the type of connection mode used for the endpoint, such as two-wire or four-wire.
Finally, the Requested Events parameter is used in MGCP messages to request that the endpoint report back on its current state or to request a specific action, such as starting or stopping a tone or announcement.
Therefore, of the given answer options, the Observed Events parameter is the most appropriate parameter in the NTFY message that is used by the MGCP gateway to inform the Cisco Unified CM that an analog endpoint has gone off-hook.