CLCOR Practice Questions 2 — 50 Questions

Question 1

You are configuring a local gateway for Webex Calling. Which mechanism ensures that the Webex Cloud can communicate with your on-premises edge device without requiring inbound firewall ports?

Accepted Answer

Outbound TLS connection from CUBE to Webex Cloud. Webex Calling Local Gateways use the Expressway-C or CUBE to establish an outbound TLS connection to the Webex cloud, removing the need for inbound port openings.

Answer

Webex Calling Connector via port forwarding

Answer

SIP Trunk over VPN

Answer

H.323 Gatekeeper registration

Question 2

You are implementing Webex Calling with a Local Gateway. The requirement is to maintain internal dial plan transparency for existing extension-to-extension dialing. What must you configure?

Accepted Answer

Location-based routing and dial plan normalization. To maintain dialing transparency, the dial plan must be synchronized or normalized between the local gateway and the Webex Calling cloud dial plan.

Answer

Global Dial Plan Replication

Answer

Directory sync override

Answer

PSTN overflow routing

Question 3

Which THREE components are involved in the Webex Hybrid Media Service architecture?

Accepted Answer

Expressway-C. The architecture relies on Expressway-C, Media nodes, and the cloud-based management platform.

Answer

Cloud PSTN Gateway

Answer

CUCM Media Resource Group

Question 4

Which protocol is primarily used by Cisco endpoints for music-on-hold (MoH) streaming from a Media Resource Group?

Accepted Answer

Multicast RTP. Multicast is the standard method for streaming MoH, as it saves significant bandwidth compared to unicast streams.

Answer

SIP INFO

Answer

HTTPS

Answer

Unicast RTSP

Question 5

Which TWO tasks must be performed when setting up Webex Hybrid Calendar service with Microsoft Exchange?

Accepted Answer

Grant the service account ApplicationImpersonation rights. You must grant service account permissions to the calendar and configure the service in Control Hub.

Answer

Create a dedicated DNS zone for Exchange

Answer

Configure a SIP trunk between Exchange and Webex

Answer

Install an H.323 gateway in the DMZ

Question 6

What is the function of a 'Device Pool' in CUCM?

Accepted Answer

To group shared settings for devices.. A Device Pool is a collection of device-specific configuration settings like location, date/time, and CM group, which can be applied to devices in bulk.

Answer

To define user permissions.

Answer

To manage media resources.

Answer

To control call routing.

Question 7

Which network condition is the most significant contributor to poor voice quality in a VoIP environment?

Accepted Answer

Jitter. Jitter, packet loss, and latency are the three main contributors to poor voice quality, but jitter (variation in packet arrival) is often the most difficult to resolve once it reaches the end device.

Answer

Low CPU usage on the router

Answer

Static IP addresses

Answer

High bandwidth usage

Question 8

In a Cisco CUCM cluster, which node is responsible for managing the database and performing configuration updates?

Accepted Answer

Publisher. The Publisher node is the primary node that holds the master database copy and handles all configuration changes.

Answer

Subscriber

Answer

TFTP node

Answer

Music on Hold (MoH) node

Question 9

You are designing a high-availability solution for Cisco Expressway. Which element is required to load-balance traffic between multiple Expressway nodes?

Accepted Answer

External Load Balancer. An external load balancer is required to distribute incoming traffic across the cluster of Expressway-E nodes.

Answer

Cisco CUBE redundancy

Answer

Cisco UCM Group

Answer

DNS Round Robin only

Question 10

When configuring a policy-map for voice traffic, which command is used to assign a specific bandwidth guarantee to a class?

Accepted Answer

bandwidth [kbps]. The 'bandwidth' command allows you to reserve a specific amount of bandwidth for a class within a policy-map.

Answer

rate-limit [kbps]

Answer

guarantee [kbps]

Answer

priority bandwidth

Question 11

What is the impact of removing a node from a Hybrid Video Mesh cluster that is currently hosting active meetings?

Accepted Answer

Active calls are dropped or experience disruption. Active meetings are disrupted. The system will attempt to re-route, but call quality will drop or the call will drop during the shift.

Answer

The node remains active until the last call ends

Answer

The cloud takes over the media immediately

Answer

The meetings are automatically migrated to another node

Question 12

A network engineer is deploying Cisco Unified Border Element (CUBE) and must ensure that voice traffic is prioritized correctly across the enterprise network. Which command correctly maps the voice traffic DSCP value to the correct priority queue in a Cisco IOS-XE router?

Accepted Answer

class-map match-any VOICE; match dscp ef; policy-map VOICE-POLICY; class VOICE; priority 1000. The 'priority' command within a policy-map defines the LLQ (Low Latency Queuing) behavior for voice traffic.

Answer

class-map match-any VOICE; match protocol sip; policy-map VOICE-POLICY; class VOICE; queue-limit 100

Answer

class-map match-all VOICE; match dscp cs4; policy-map VOICE-POLICY; class VOICE; bandwidth 1000

Answer

class-map match-any VOICE; match dscp ef; policy-map VOICE-POLICY; class VOICE; fair-queue

Question 13

A collaboration designer must ensure that inter-cluster calls between two CUCM clusters remain secure. Which mechanism must be implemented to ensure media remains encrypted from end to end?

Accepted Answer

Ensure SRTP is enabled on the SIP Trunk Security Profile.. SRTP must be used across the SIP inter-cluster trunk to ensure the media stream is encrypted between endpoints in different clusters.

Answer

Disable SIP inspection on the firewalls.

Answer

Configure a VPN between the two clusters.

Answer

Enable MTP (Media Termination Point) for all calls.

Question 14

Which TWO of the following are valid methods for connecting on-premises PSTN to Webex Calling?

Accepted Answer

Local Gateway. The two primary methods are the Local Gateway (via CUBE/Expressway) and Cloud Connected PSTN (CCP).

Answer

Direct SIP to CUCM

Answer

H.323 Trunking

Answer

Webex Edge for Calling

Question 15

You are verifying the network readiness for a Cisco TelePresence endpoint. Which tool would you use to measure the packet loss, latency, and jitter on the path to the CUCM cluster?

Accepted Answer

IP SLA. IP SLA (Service Level Agreement) is the Cisco IOS feature used to generate synthetic traffic to measure network performance metrics.

Answer

NetFlow

Answer

SNMP

Answer

SPAN

Question 16

If a Translation Pattern is configured in CUCM, at what stage of the call processing does the digit manipulation occur?

Accepted Answer

Before the Route Pattern is matched.. Translation Patterns act as a mid-call processing step. When a digit string is dialed, CUCM checks for Translation Patterns before checking Route Patterns.

Answer

After the call is sent to the gateway.

Answer

At the device level during registration.

Answer

Only when the call fails to route.

Question 17

In a multisite WAN deployment, which codec should you choose to balance voice quality and bandwidth consumption across a constrained link?

Accepted Answer

G.729. G.729 is the standard low-bandwidth codec that provides acceptable voice quality at 8kbps.

Answer

G.711

Answer

AAC-LD

Answer

G.722

Question 18

You are troubleshooting a registration failure for a remote IP phone. The phone is configured to use an Expressway-E for MRA. Which DNS record is queried by the client to find the Expressway-E cluster?

Accepted Answer

_collab-edge._tls. The _collab-edge._tls DNS SRV record is the first step in the MRA discovery process to locate the Expressway-E.

Answer

_cisco-uds._tcp

Answer

_sip._tls

Answer

_tftp._udp

Question 19

When deploying Cisco IP phones, what is the best practice for VLAN configuration?

Accepted Answer

Use a dedicated Voice VLAN.. Phones should be placed in a dedicated Voice VLAN for security and QoS performance reasons.

Answer

Use the default VLAN 1 for all voice and data.

Answer

Use a separate physical switch for phones.

Answer

Do not use VLANs; use static routing.

Question 20

In the context of collaboration design, what is the purpose of the 'Location' in CUCM?

Accepted Answer

Call Admission Control. Locations are used for Call Admission Control (CAC) to limit the bandwidth consumed by calls traversing a specific path.

Answer

Defining physical building layouts

Answer

Device registration grouping

Answer

TFTP file distribution