Users are complaining that they hear echo when they place calls to the PSTN through the HQ_PSTN gateway. The voice port configuration for the gateway is as follows:

voice-port 1/0:23
input gain -1
output attenuation 1
echo-cancel erl worst-case 3

Why are users hearing echo?

You are troubleshooting why a user cannot make calls to the PSTN. You are reviewing trace files and you have found where the user’s IP phone initiates the call but you never see the call go out the gateway. What is the next step in troubleshooting this issue?

You have received a trouble ticket stating that users in accounting are not able to use the CFwdAll softkey to forward their calls to voice mail. Their phones continue to ring when they receive inbound calls,even after they have pressed the CFwdAll softkey and the Messages button. What is a possible cause of this issue?

The following is a partial configuration of an access layer switch:

mls qos map cos-dscp 0 8 12 16 28 32 40 48
mls qos
!

Voice bearer traffic will be set to use which per-hop behavior?

LSC validation is failing on a new SCCP IP phone you have just added to the Cisco Unified CallManager 5.0 cluster. No other IP phones are experiencing any problems with LSC validation.What can you do to help pinpoint the problem?

You have added a subscriber server to your Cisco Unified CallManager 5.0 cluster. The server is functioning properly, but regular updates from the publisher are failing. All other publisher-subscriber communications are working properly in the cluster.What is the problem?

You are the network technician of your company. And you have just received a trouble ticket stating that three calls have successfully been made across a WAN link. However, when making the fourth call, the quality of all calls is lowered. Which QoS mechanism can prevent this problem?

Which log file contains call-processing information from services such as Cisco Unified CallManager and Cisco Unified CallManager CTI Manager?

Refer to the exhibit.

You have received a trouble ticket stating that calls to international numbers are failing. To place an international call, users dial the access code “9,” followed by “011,” the country code, and the destination number. After entering the debug isdn q931 command on the MGCP gateway, you have the user attempt the call again.Based on the debug output, what is the most likely cause of this problem?

Refer to the exhibit.

You have received a trouble ticket stating that calls to international numbers are failing. To place an international call, users dial the access code “9,” followed by “011,” the country code, and the destination number. After entering the debug isdn q931 command on the MGCP gateway, you have the user attempt the call again.
Based on the debug output, what is the most likely cause of this problem?