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Cisco 642-432 Exam - Testking Free 642-432 Sample Questions: 1.You are working with a potential customer that would like to integrate its existing PBX telephone system into its IP network. The accompanying figure shows that the customer has two offices that need to be connected to the IP network so that the customer can exchange telephone calls without using the PSTN. Both PBXs are currently connected to T1 ISDN circuits. Which signaling type will allow you to support your customer?
A.QSIG
B.CCS
C.CAS
D.TCCS
E.E&M
F.FXO
Answer: C
2.You are meeting with a customer that has deployed IP telephony at their headquarters location. They would like to roll out IP telephony to their regional office as well. They are now using the G.711 codec at headquarters. They want to be able to maximize the number of calls carried without impacting voice quality or forcing a WAN upgrade. Which codec would be appropriate for their WAN?
A.G.726
B.G.723.1
C.G.711
D.G.729B
Answer: D
3.Refer to the exhibit. Users are not able to complete a call from 6785551212 to 7705551111. What is the correct diagnosis for the problem?
A.incorrect dialpeer statement in Router 1
B.incorrect port statement in Router 1 pots dial peer
C.incorrect sessiontarget statement in Router 2
D.incorrect destinationpattern in Router 1
Answer: D
4.You have been forwarded some questions by a prospective VoIP customer who would like to know the Cisco default sample size for the G.729 codec. What is it?
A.40 ms
B.30 ms
C.20 ms
D.10 ms
Answer: C
5.Examine the example output. hostname GW1 ! interface Ethernet 0/0 ip address 172.16.2.1
255.255.255.0 h323gateway voip interface h323gateway voip id GK1zone1.abc.com abc.com ipaddr 172.16.2.2 h323gateway voip h323id GW1 h323gateway voip bind srcaddr 172.16.2.1 ! dialpeer voice 1 voip destinationpattern 1212. sessiontarget ras ! dialpeer voice 2 pots destinationpattern 2125551212 no register e164 ! end Choose the command that will restore communication with gatekeeper functionality to this device.
A.h323gateway voip h323id GK1
B.gateway
C.h323gateway voip bind srcaddr 172.16.2.2
D.h323gateway voip GW1zone2.abc.com abc.com ipaddr 172.16.2.1
Answer: B
6.Which preference key word assigns top precedence to a dial peer in a huntgroup?
A.0
B.priority
C.1
D.high
Answer: A
7.Which type of delay is caused when large data packets block voice packets from the outbound interface?
A.queuing delay
B.serialization delay
C.propagation delay
D.packetization delay
Answer: A
8.A 9 digit number must be dialed to reach numbers on the PSTN. What process makes sure that the first digit 9 is not transmitted as part of the called number?
A.digit alternating
B.digit masking
C.digit manipulation
D.digit seizing
Answer: C
9.What is the E.164 numbering plan?
A.a proprietary PBX number plan
B.the IETF North American number plan
C.the European PBX standard telephony number plan
D.the ITU worldwide number plan
Answer: D
10.Refer to the exhibit. What is the minimum WAN bandwidth required to support three simultaneous VoIP calls in this network?
A.19,200 bps
B.51,600 bps
C.79,200 bps
D.247,200 bps
Answer: B
11.In the connection between a Cisco router and an E&M port on a PBX, which side is generally the Cisco side?
A.loop start
B.trunk circuit
C.switch port
D.signaling unit
Answer: D
12.Which dial plan characteristic shows the most obvious improvement by dropping a number translation step?
A.availability
B.postdial delay
C.scalability
D.hierarchical design
Answer: B
13.What are two basic parameters needed to setup a dial peer connected to the PSTN? (Choose two.)
A.voice port
B.signaling type
C.interface bandwidth
D.destination pattern
Answer: A, D
14.Which device is used to allow an H.323 stream to transit a firewall?
A.gatekeeper
B.gateway
C.proxy
D.MCU
Answer: C
15.You are working with your customer in their lab to test the effect of jitter on voice quality. You have set the maximum playout delay to 40 ms on the voice enabled routers. What will be the impact on voice quality if after severe congestion the playout buffer empties and the source sends packets to the buffer faster than they are leaving?
A.There will be no noticeable drop in quality.
B.The jitter buffer will adapt to the fasterarriving packets by expanding the buffer size.
C.The jitter buffer will speed up delivery of packets to the DSP so that packets are not dropped.
D.After the jitter buffer fills up, subsequent packets are discarded.
Answer: D
16.Refer to the exhibit. Your customer wants to converge voice and data on the existing T1 Frame Relay WAN link between New York and Atlanta. The customer has allocated 25 percent of the WAN link for routing updates and other overhead. You are using 6 bytes of overhead for Frame Relay, no cRTP, and the G.729 codec. How many calls could be placed on this link?
A.two
B.three
C.four
D.five
E.six
F.seven
Answer: C
17.In a VoIP environment when speech samples are framed every 20 ms, a payload of 20 bytes is generated. Assuming a total packet length of 60 bytes, what is the length of the packet header if cRTP is deployed without redundancy checks?
A.1 byte
B.2 bytes
C.3 bytes
D.4 bytes
E.20 bytes
F.40 bytes
Answer: B
18.You have a customer that is interested in determining the number of VoIP calls their Frame Relay WAN links can support. Each of their Frame Relay WAN links has 84 kbps of bandwidth available outside all other applications and overhead. How many G.729 calls using the 8 kbps codec and 20 byte sample size can be supported?
A.1
B.2
C.3
D.4
Answer: C |
