CLCOR Practice Exam 4 — 20 Questions

Question 1

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 2

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 3

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 4

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 5

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 6

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 7

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 8

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 9

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 10

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

Question 11

You are deploying a Cisco Expressway-E in a DMZ. Which port must be opened on the external firewall to allow for H.460.18/19 firewall traversal for H.323 endpoints?

Accepted Answer

1720. Port 1720 is the standard H.323 signaling port used for traversal through the Expressway-E.

Answer

5061

Answer

8080

Answer

443

Question 12

When designing a secure collaboration network, what is the best practice for handling certificates in a CUCM and Expressway cluster?

Accepted Answer

Use a trusted third-party CA for all servers.. Using a trusted, third-party Certificate Authority (CA) ensures that all certificates are valid across both internal and external endpoints without security warnings.

Answer

Use self-signed certificates on all nodes.

Answer

Disable certificate verification on all endpoints.

Answer

Use the Publisher as the CA for the entire network.

Question 13

Which THREE of the following are required DNS records for a successful Cisco MRA (Mobile and Remote Access) deployment?

Accepted Answer

_cisco-uds._tcp. MRA relies on SRV records for discovering the Expressway-E, the Collab-Edge TLS record for discovery, and the UDS service record for user settings.

Answer

_https._udp

Answer

_ftp._tcp

Question 14

You are designing a network for video collaboration. What is the recommended maximum one-way latency for high-quality video conferencing?

Accepted Answer

150ms. For high-quality, real-time video conferencing, one-way latency must be kept below 150ms to ensure a good user experience.

Answer

300ms

Answer

500ms

Answer

50ms

Question 15

Which TWO of the following are considered best practices for implementing QoS in a Cisco collaboration network?

Accepted Answer

Mark traffic as close to the source as possible. Cisco recommends using trust boundaries and marking traffic as close to the source as possible.

Answer

Trust all incoming traffic by default

Answer

Only mark traffic at the WAN edge

Answer

Disable all QoS policies to improve performance

Question 16

Which TWO of the following are essential components of a Cisco network readiness assessment for collaboration?

Accepted Answer

Bandwidth capacity analysis. Assessing existing bandwidth capacity and ensuring QoS settings are correctly applied are the two primary foundations for a network readiness assessment.

Answer

Analyzing NTP Stratum levels

Answer

Verifying phone firmware versions

Answer

Checking IP address assignment

Question 17

You have a cluster with multiple nodes. You want to ensure that phones in the 'New York' office prioritize registration to a 'New York' subscriber. How do you implement this?

Accepted Answer

Create a CM Group with the local subscribers and assign it to the Device Pool.. By creating a specific CM Group with the New York subscribers in the preferred order and assigning it to the New York Device Pool.

Answer

Use a Route Group to point to the subscriber.

Answer

Assign the phones to a specific Region.

Answer

Configure the TFTP server address in the phone.

Question 18

Which THREE of the following items must be verified during a site-to-site VPN check for collaboration traffic?

Accepted Answer

MTU size. MTU sizes (to avoid fragmentation), DSCP tag preservation (to maintain QoS), and UDP port ranges (for RTP media) are critical for successful inter-site communication.

Answer

DHCP relay configuration

Answer

NTP server reachability

Question 19

Which service must be running for a Cisco IP Phone to download its configuration file via TFTP?

Accepted Answer

Cisco TFTP. The Cisco TFTP service is responsible for providing configuration files and firmware updates to registered devices.

Answer

Cisco CallManager

Answer

Cisco CTIManager

Answer

Cisco Database Layer Monitor

Question 20

Which component in the CUCM dial plan allows you to match a pattern and simultaneously transform it into a new number before the final route lookup?

Accepted Answer

Translation Pattern. A Translation Pattern is used to change digits (e.g., adding an access code) before the call is routed to a final destination.

Answer

Route Pattern

Answer

Partition

Answer

Route Group