Cisco 642-427 Online Practice Questions and Exam Preparation

Cisco 642-427 Online Questions & Answers

• Question 251:

  Up to 10 phone calls over a 1 Mb/s WAN link have had consistently acceptable audio quality, even with considerable data traffic. Recently, when over 10 calls are made, audio quality has declined. Which solution would you implement to maintain acceptable audio quality for the first 10 calls only while allowing for changes in WAN data utilization?

  A. Cisco Unified Communications Manager CAC
  B. RSVP CAC on the routers integrated with Cisco Unified Communications Manager
  C. CAC implemented directly on the Cisco IP Phones
  D. RSVP CAC operating on the routers independently of Cisco Unified Communications Manager
  B. RSVP CAC on the routers integrated with Cisco Unified Communications Manager

• Question 252:

  Which option can cause an offnet call to fail?

  A. voice codec mismatch
  B. IP subnet mismatch
  C. phone protocol mismatch
  D. phone type mismatch
  A. voice codec mismatch

• Question 253:

  Three calls can successfully be made across a WAN link. When a fourth call is made, the quality of all four calls degrades. Which QoS mechanism can help avoid this problem?

  A. CAC
  B. FRF.12
  C. LFI
  D. LLQ
  E. priority queuing
  A. CAC

• Question 254:

  How does LLQ ensure that voice traffic is always expedited?

  A. LLQ adds a strict priority class to CBWQF. The class allows delay-sensitive data such as voice to be dequeued and sent first.
  B. LLQ uses CBWFQ to prioritize voice traffic and dequeue the voice packets so that they can be handled first.
  C. The strict priority queue has a higher weight than the queues in CBWFQ. This weight allows the delay sensitive data such as voice to be dequeued and sent first.
  D. The LLQ strict priority queue allows delay-sensitive data such as voice to be dequeued and sent first (before packets in order queue are dequeued), giving delay sensitive data preferential treatment over other traffic.
  D. The LLQ strict priority queue allows delay-sensitive data such as voice to be dequeued and sent first (before packets in order queue are dequeued), giving delay sensitive data preferential treatment over other traffic.

• Question 255:

  Which two phones work in Cisco Unified Communications Manager Device Mobility? (Choose two.)

  A. phones with an IP address assigned using NAT/PAT
  B. phones with an IP address assigned by DHCP
  C. phones with an IP Addressing Mode set to IPv4 Only
  D. phones with an IP Addressing Mode set to IPv6 Only
  B. phones with an IP address assigned by DHCP
  C. phones with an IP Addressing Mode set to IPv4 Only

• Question 256:

  Given the following configuration, what IP address will GK1 use to send and receive RAS messages?

  GK1 (config)#interface serial 0/0/0 GK1 (config-if)#ip address 192.168.0.2 255.255.255.0 GK1 (config-if)#exit GK1 (config)#interface serial 0/0/1 GK1 (config-if)#ip address 172.16.0.2 255.255.255.0 GK1 (config-if)#exit GK1 (config)#gatekeeper GK1 (config-gk)#zone local SanJose cisco.com 172.16.0.2 GK1 (config-gk)#zone remote Austin cisco.com 192.168.0.1 GK1 (config-gk)#zone prefix SanJose 2... GK1 (config-gk)#zone prefix Austin 3...

  A. 192.168.0.2
  B. 172.16.0.2
  C. 192.168.0.1
  D. RAS messages will be load balanced between 192.168.0.2 and 172.16.0.2
  B. 172.16.0.2

• Question 257:

  If you need to avoid choppy speech, what is the maximum tolerable round-trip delay between two VoIP endpoints?

  A. 100 ms
  B. 200 ms
  C. 300 ms
  D. 400 ms
  E. 500 ms
  F. 800 ms
  C. 300 ms

• Question 258:

  Cisco IP Phones are being installed on several different IP subnets in a new Cisco Unified Communications Manager installation. Phones are not registering to Cisco Unified CM. Which three DHCP options must be set properly in each subnet for all phones to register to Cisco Unified Communications Manager? (Choose three.)

  A. IP address and subnet mask
  B. DNS server
  C. option 150
  D. default gateway
  E. WINS server
  A. IP address and subnet mask
  C. option 150
  D. default gateway

• Question 259:

  Refer to the exhibit. A user is on a call to the PSTN through the MGCP gateway at BR1. The gateway and the IP phone lose the connection to the Cisco Unified CallManager cluster at HQ and the call is dropped. What is causing the call to be dropped?

  

  A. The CallManager cluster has lost control of the D channel on the PRI gateway at BR1.
  B. SRST has not been configured on the BR1 gateway.
  C. The IP phone has not registered with SRST.
  D. The no h225 timeout keepalive command has not been configured on the gateway.
  A. The CallManager cluster has lost control of the D channel on the PRI gateway at BR1.

• Question 260:

  Your manager requires that users who call PSTN phones from Cisco IP Phones in a Cisco Unified Communications Manager cluster have the single caller ID of 13125551000 for the entire company. Which approach achieves this goal?

  A. Change the external phone number mask on all phones to 13125551000.
  B. Create a route pattern in Cisco Unified Communications Manager of 13125551000.
  C. Create a VoIP dial peer to Cisco Unified Communications Manager with the destination pattern of 13125551000.
  D. Configure the gatekeeper to change the caller number to 13125551000.
  A. Change the external phone number mask on all phones to 13125551000.