642-453 exam tests a candidate knowledge of the implementation of Cisco gateways and gatekeepers, including integration of a VoIP network to both PSTN and TDM equipment. Topics covered include implementing dial plans and advanced gateway features such as SRST and DSP resources, implementing gatekeepers and directory gatekeepers to provide hierarchical dial plan resolution, and call admission control.

Explain the function and interoperation of voice & video Gateways within an Cisco Certification IP Communications network
Describe the function and interoperation of Gatekeepers within an IP Communications network
Implement a Gatekeeper
Implement a Gateway
Implement a dial-plan
Implement call applications on a Gateway
Implement an IP-to-IP Gateway

Exam : CISCO 642-453
Title : Gateway Gatekeeper(GWGK)
1. You are adding a gatekeeper to an H.323 network to provide Call Admission Control. You need to be able to support three concurrent G.711 calls from a specified zone to any other zone. How much interzone bandwidth should be configured in the gatekeeper?
A. 192 Kbps
B. 240 Kbps
C. 384 Kbps
D. 480 Kbps
Answer: C
2. Refer to the exhibit. Your customer is using BRIs to the PSTN. Inbound calls can be made without error. However, outbound calls only succeed if there has been a recent inbound call. What can be done to correct this issue?
A. Disable status checking for POTS dial peers so outbound call setup will activate the BRI.
B. Configure SPIDs on the BRI so that outbound calls are sent to the correct number.
C. Change the dial peer hunt logic so the appropriate dial peer is always used.
D. Configure preferences to always select dial peer 3.
Answer: A

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