Cisco 400-051 Online Practice Questions and Exam Preparation

Cisco 400-051 Online Questions & Answers

• Question 41:

  Auto-registration is enabled on a mixed-mode Cisco Unified Communications Manager with software version 11.0. A new Cisco 7965 SCCP IP Phone just downloaded the default phone configuration file from the TFTP server in the cluster. Which result is true?

  A. The IP phone attempts to auto-register with the highest priority Cisco UCM node on the default phone configuration file, but the registration is rejected.
  B. The IP phone attempts to auto-register with a Cisco UCM node UCM1, and the registration is rejected.
  C. The IP phone attempts to auto-register with TFTP server, and the registration is rejected.
  D. The IP phone attempts to auto-register with the highest priority Cisco UCM node on the default phone configuration file, and the registration is successful.
  E. The IP phone does not attempt to auto-register.
  D. The IP phone attempts to auto-register with the highest priority Cisco UCM node on the default phone configuration file, and the registration is successful.

• Question 42:

  In Channel Associated Signaling on a T1 circuit using Extended Super Frame, how many signaling bits does each T1 timeslot have?

  A. 1
  B. 2
  C. 4
  D. 12
  E. 24
  C. 4

  ---

  Each T1 channel carries a sequence of frames. These frames consist of 192 bits and an additional bit designated as the framing bit, for a total of 193 bits per frame. Super Frame (SF) groups twelve of these 193 bit frames together and designates the framing bits of the even numbered frames as signaling bits. CAS looks specifically at every sixth frame for the timeslot's or channel's associated signaling information. These bits are commonly referred to as A- and B-bits. Extended super frame (ESF), due to grouping the frames in sets of twenty-four, has four signaling bits per channel or timeslot. These occur in frames 6, 12, 18, and 24 and are called the A-, B-, C-, and D-bits respectively.

  References: Reference: http://www.cisco.com/c/en/us/support/docs/voice/digital-cas/22444-t1-cas-ios.html

• Question 43:

  Which four attributes are needed to determine the time to complete a TFTP file transfer process? (Choose four.)

  A. file size
  B. file type
  C. network interface type
  D. round-trip time
  E. packet loss percentage
  F. response timeout
  G. network throughput
  A. file size
  D. round-trip time
  E. packet loss percentage
  F. response timeout

  ---

  Four attributes that are needed to determine the time to complete TFTP file transfer process is:

  1.

  File Size

  2.

  Round-trip time

  3.

  Packet loss percentage

  4.

  Response timeout References: http://www.cisco.com/en/US/prod/collateral/voicesw/ps6882/ps6884/white_paper_c11-583891_ps10451_Products_White_Paper.html

• Question 44:

  Which statement describes the external database requirement for the Cisco IM and Presence permanent group chat feature?

  A. All nodes in a Cisco IM and Presence cluster can share a physical external database.
  B. All nodes in a Cisco IM and Presence cluster can share a logical external database.
  C. Each node in a Cisco IM and Presence cluster must have its own physical external database.
  D. Each node in a Cisco IM and Presence cluster must have its own logical external database.
  E. An external database is not mandatory.
  D. Each node in a Cisco IM and Presence cluster must have its own logical external database.

  ---

  When you configure an external database entry on IM and Presence, you assign the external database to a node, or nodes, in your cluster as follows:

  For the Compliance feature, you require at least one external database per cluster. Depending on your deployment requirements, you can also configure a separate external database per node.

  For the Permanent Group Chat feature, you require a unique external database per node. Configure and assign a unique external database for each node in your cluster.

  If you deploy both the Permanent Group Chat and Compliance features on an IM and Presence node, you can assign the same external database to both features.

• Question 45:

  Which two are characteristics of jitter buffers? (Choose two.)

  A. Jitter buffers are used to change asynchronous packet arrivals into a synchronous stream by turning variable network delays into constant delays at the destination end systems.
  B. Jitter buffers are used to change asynchronous packet arrivals into a synchronous stream by turning variable network delays into constant delays at the sending systems.
  C. The role of the jitter buffer is to balance the delay and the probability of interrupted playout due to late packets.
  D. The role of the jitter buffer is to queue late packets and reorder out-of-order packets.
  E. Jitter buffers are used to change asynchronous packet arrivals into a synchronous stream by queuing packets into constant delays at the sending systems.
  A. Jitter buffers are used to change asynchronous packet arrivals into a synchronous stream by turning variable network delays into constant delays at the destination end systems.
  C. The role of the jitter buffer is to balance the delay and the probability of interrupted playout due to late packets.

  ---

  Jitter buffers are used to remove the effects of jitter so that asynchronous packet arrivals are changed to a synchronous stream. The jitter buffer trades off between delay and the probability of interrupted playout because of late packets (discard).

  References: http://www.appneta.com/blog/jitter-voip/

• Question 46:

  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.
  A. The ephone hunt group is mandatory.
  C. Hunt group members must be SCCP IP phones.

  ---

  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.

  References: http://www.cisco.com/en/US/docs/voice_ip_comm/cucme/command/reference/cme_v1ht.html

• Question 47:

  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
  B. Real-time Interactive

  ---

  Telepresence is used for video conferencing which can be done in Real-time so it is Real-time Interactive.

• Question 48:

  The CIO has approached the lead architects to launch a new business transformation service across the entire organization. It requires adding thousands of virtualized container entities to the private and public cloud environment. But this carries a significant management hurdle in organizing and tracking large number of container instances. Which five solutions do you use to overcome this problem? (Choose five.)

  A. Red Hat OpenShift
  B. Deis
  C. Kubernetes
  D. Amazon ECS
  E. Cisco UCS Director
  F. Docker Compose and Swarm
  G. Open Daylight
  H. Prime Catalog
  A. Red Hat OpenShift
  C. Kubernetes
  D. Amazon ECS
  E. Cisco UCS Director
  F. Docker Compose and Swarm

• Question 49:

  Which option is a characteristic of the Enhanced Location Call Admission Control mechanism on Cisco Unified Communications Manager?

  A. It accounts for network protocol rerouting.
  B. It accounts for network downtime and failures.
  C. It supports dynamic bandwidth adjustments based on WAN topology changes.
  D. It supports asymmetric media flows such that different bit rates in each direction are deducted accordingly.
  E. Unidirectional media flows are deducted as if they were bidirectional.
  E. Unidirectional media flows are deducted as if they were bidirectional.

  ---

  Network Modeling with Locations, Links, and Weights Enhanced Location CAC is a model-based static CAC mechanism. Enhanced Location CAC involves using the administration interface in Unified CM to configure Locations and Links to model the "Routed WAN Network" in an attempt to represent how the WAN network topology routes media between groups of endpoints for end-to-end audio, video, and immersive calls. Although Unified CM provides configuration and serviceability interfaces in order to model the network, it is still a "static" CAC mechanism that does not take into account network failures and network protocol rerouting. Therefore, the model needs to be updated when the WAN network topology changes. Enhanced Location CAC is also call oriented, and bandwidth deductions are per-call not per-stream, so asymmetric media flows where the bit-rate is higher in one direction than in the other will always deduct for the highest bit rate. In addition, unidirectional media flows will be deducted as if they were bidirectional media flows.

  References: http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/srnd/collab10/collab10/cac.html

• Question 50:

  What is the default data collection interval for Call Detail Records on Cisco Unified CM?

  A. 60 seconds
  B. 1 seconds
  C. 1440 seconds
  D. 600 seconds
  E. 3600 seconds
  A. 60 seconds

  ---

  CDR File Time Interval This parameter specifies the time interval for collecting CDR data. For example, if this value is set to 1, each file will contain 1 minute of CDR data (CDRs and CMRs, if enabled). The CDR database will not receive the data in each file until the interval has expired, so consider how quickly you want access to the CDR data when you decide what interval to set for this parameter. The minimum value is 1 (which is also the default). Maximum is 1440. The unit of measure for this required field represents a minute. References: