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QUESTION 41
Which two statements are requirements regarding hunt group options for B-ACD implementation on Cisco Unified Communications Manager Express routers? (Choose two.)
A. The ephone hunt group is mandatory.
B. Either the ephone hunt group or the voice hunt group is acceptable.
C. Hunt group members must be SCCP IP phones.
D. Hunt group members can include both SCCP or SIP IP phones.
E. Hunt group members must be SIP IP phones.
F. The member hunting mechanism must be set to sequential.
Answer: AC
Explanation:
The ephone hunt group is mandatory, and while ephone hunt groups only support Cisco Unified SCCP IP phones, a voice hunt group supports either a Cisco Unified SCCP IP phone or a Cisco Unified SIP IP phone.
http://www.cisco.com/en/US/docs/voice_ip_comm/cucme/command/reference/cme_v1ht.html
QUESTION 42
Which call hunt mechanism is only supported by the voice hunt group in a Cisco Unified Communications Manager Express router?
A. sequential
B. peer
C. longest idle
D. parallel
E. overlay
Answer: D
Explanation:
Parallel Hunt-Group, allows a user to dial a pilot number that rings 2-10 different extensions simultaneously. The first extension to answer gets connected to the caller while all other extensions will stop ringing. A timeout value can be set whereas if none of the extensions answer before the timer expires, all the extensions will stop ringing and one final destination number will ring indefinitely instead. The final number could be another voice hunt-group pilot number or mailbox The following features are supported for Voice Hunt-Group:
Calls can be forwarded to Voice Hunt-Group
Calls can be transferred to Voice Hunt-Group
Member of Voice Hunt-Group can be SCCP, ds0-group, pri-group, FXS or SIP phone/trunk
Max member of Voice Hunt-Group will be 32
QUESTION 43
Which Cisco Unified Communications Manager Express ephone button configuration separator enables overflow lines when the primary line for an overlay button is occupied by an active call?
A. o
B. c
C. w
D. x
E. :
Answer: D
Explanation:
x expansion/overflow, define additional expansion lines that are used when the primary line for an overlay button is occupied by an active call.
QUESTION 44
Which two statements describe characteristics of Cisco Unified Border Element high availability, prior to Cisco IOS release 15.2.3T, using a box-to-box redundancy configuration? (Choose two.)
A. It leverages HSRP for router redundancy and GLBP for load sharing between a pair of routers.
B. Cisco Unified Border Element session information is check-pointed across the active and standby router pair.
C. It supports media and signal preservation when a switchover occurs.
D. Only media streams are preserved when a switchover occurs.
E. It can leverage either HSRP or VRRP for router redundancy.
F. The SIP media signal must be bound to the loopback interface.
Answer: BD
QUESTION 45
Refer to the exhibit. From this NFAS-enabled T1 PRI configuration on a Cisco IOS router, how many bearer channels are available to carry voice traffic?
A. 91
B. 92
C. 93
D. 94
E. 95
Answer: D
Explanation:
In NFAS one channel is used for signaling so according to this we will have 94 channel for with bearer capability.
QUESTION 46
Refer to the exhibit. Assuming this NFAS-enabled T1 PRI configuration on a Cisco IOS router is fully functional, what will the controller T1 1/1 D-channel status be in the output of the show isdn status command?
A. MULTIPLE_FRAME_ESTABLISHED
B. TEI_ASSIGNED
C. AWAITING_ESTABLISHMENT
D. STANDBY
E. INITIALIZED
Answer: B
Explanation:
TEI_ASSIGNED, which indicates that the PRI does not exchange Layer 2 frames with the switch. Use the show controller t1 x command to first check the controller t1 circuit, and verify whether it is clean (that is, it has no errors) before you troubleshoot ISDN Layer 2 problem with the debug isdn q921.
QUESTION 47
Refer to the exhibit. In an effort to troubleshoot a caller ID delivery problem, a customer emailed you the voice port configuration on a Cisco IOS router. Which type of voice port is it?
A. FXS
B. E&M
C. BRI
D. FXO
E. DID
Answer: D
QUESTION 48
The iLBC codec operates at 38 bytes per sample per 20-millisecond interval. What is its codec bit rate in kilobits per second?
A. 6.3
B. 13.3
C. 15.2
D. 16
E. 24
Answer: C
Explanation:
The internet Low Bit Rate Codec (iLBC) is designed for narrow band speech and results in a payload bit rate of 13.33 kbits per second for 30-millisecond (ms) frames and 15.20 kbits per second for 20 ms frames. When the codec operates at block lengths of 20 ms, it produces 304 bits per block, which is packetized as defined in RFC 3952. Similarly, for block lengths of 30 ms it produces 400 bits per block, which is packetized as defined in RFC 3952.The iLBC has built-in error correction functionality to provide better performance in networks with higher packet loss.
QUESTION 49
Assume 6 bytes for the Layer 2 header, 1 byte for the end-of-frame flag, and a 40-millisecond voice payload, how much bandwidth should be allocated to the strict priority queue for five VoIP calls that use a G.729 codec over a multilink PPP link?
A. 87 kb/s
B. 134 kb/s
C. 102.6 kb/s
D. 77.6 kb/s
E. 71.3 kb/s
Answer: A
Explanation:
Voice payloads are encapsulated by RTP, then by UDP, then by IP. A Layer 2 header of the correct format is applied; the type obviously depends on the link technology in use by each router interface: A single voice call generates two one-way RTP/UDP/IP packet streams. UDP provides multiplexing and checksum capability; RTP provides payload identification, timestamps, and sequence numbering.
QUESTION 50
Assume 20 bytes of voice payload, 6 bytes for the Layer 2 header, 1 byte for the end-of-frame flag, and the IP, UDP, and RTP headers are compressed to 2 bytes, how much bandwidth should be allocated to the strict priority queue for six VoIP calls that use a G.729 codec over a multilink PPP link with cRTP enabled?
A. 80.4 kb/s
B. 91.2 kb/s
C. 78.4 kb/s
D. 69.6 kb/s
E. 62.4 kb/s
Answer: D
Explanation:
Voice payloads are encapsulated by RTP, then by UDP, then by IP. A Layer 2 header of the correct format is applied; the type obviously depends on the link technology in use by each router interface: A single voice call generates two one-way RTP/UDP/IP packet streams. UDP provides multiplexing and checksum capability; RTP provides payload identification, timestamps, and sequence numbering.
QUESTION 51
To which QoS tool category does compressed RTP belong?
A. classification
B. marking
C. link efficiency
D. queuing
E. prioritization
Answer: C
Explanation:
LLQ is a feature that provides a strict PQ to CBWFQ. LLQ enables a single strict PQ within CBWFQ at the class level. With LLQ, delay-sensitive data (in the PQ) is dequeued and sent first. In a VoIP with LLQ implementation, voice traffic is placed in the strict PQ.
QUESTION 52
How are queues serviced in Cisco IOS routers with the CBWFQ algorithm?
A. first-in, first-out
B. weighted round robin based on assigned bandwidth
C. strict priority based on assigned priority
D. last-in, first-out
E. weighted round robin based on assigned priority
Answer: B
Explanation:
Class Based Weighted Fair queuing is an advanced form of WFQ that supports user defined traffic classes I.e. one can define traffic classes based on match criteria like protocols, access control lists (ACLs), and input interfaces. A flow satisfying the match criteria for a class contributes the traffic for that particular defined class. A queue is allocated for each class, and the traffic belonging to that class is directed to the queue for that class.
QUESTION 53
In Cisco IOS routers that use low latency queuing, which algorithm is used to presort traffic going into the default queue?
A. first-in, first-out
B. last-in, first-out
C. weighted round robin
D. fair queuing
E. random processing
Answer: D
Explanation:
WFQ is a flow-based queuing algorithm used in Quality of Service (QoS) that does two things simultaneously: It schedules interactive traffic to the front of the queue to reduce response time, and it fairly shares the remaining bandwidth between high bandwidth flows. A stream of packets within a single session of a single application is known as flow or converstion. WFQ is a flow-based method that sends packets over the network and ensures packet transmission efficiency which is critical to the interactive traffic. This method automatically stabilizes network congestion between individual packet transmission flows.
QUESTION 54
Which statement describes the Cisco best practice recommendation about priority queue bandwidth allocation in relationship to the total link bandwidth when multiple strict priority LLQs are configured on the same router interface?
A. Each LLQ should be limited to one-third of the link bandwidth capacity.
B. The sum of all LLQs should be limited to two-thirds of the link bandwidth capacity.
C. The sum of all LLQs should be limited to one-half of the link bandwidth capacity.
D. The sum of all LLQs should be limited to one-third of the link bandwidth capacity.
E. Cisco does not recommend more than one strict priority LLQ per interface.
Answer: D
Explanation:
Cisco Technical Marketing testing has shown a significant decrease in data application response times when Real-Time traffic exceeds one-third of a link’s bandwidth capacity. Cisco IOS Software allows the abstraction (and, thus, configuration) of multiple LLQs. Extensive testing and production-network customer deployments have shown that limiting the sum of all LLQs to 33 percent is a conservative and safe design ratio for merging real-time applications with data applications.
QUESTION 55
To which Cisco enterprise medianet application class does Cisco TelePresence belong?
A. VoIP Telephony
B. Real-time Interactive
C. Multimedia Conferencing
D. Broadcast Video
E. Low Latency Data
Answer: B
Explanation:
Telepresence is used for video conferencing which can be done in Real-time so it is Real-time Interactive.
New 400-051 exam questions from PassLeader 400-051 dumps! Welcome to download the newest PassLeader 400-051 VCE and PDF dumps: http://www.passleader.com/400-051.html (661 Q&As~~~2019 NEW VERSION!!!)
P.S. Free 400-051 dumps are available on Google Drive shared by PassLeader: https://drive.google.com/open?id=0B-ob6L_QjGLpNnliRG04bG9GbEk
