CLCOR Practice Test 9 — 10 Questions

Question 1

A collaboration engineer is deploying Webex Hybrid Calling with Cisco Unified Communications Manager (CUCM) as the call control. The engineer wants to provide PSTN access to Webex Calling users by leveraging the existing on-premises Cisco IOS Voice Gateway. Which solution should be implemented?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

Cisco Unified Border Element (CUBE) with Local Gateway. Local Gateway is the correct hybrid PSTN solution when an organization wants to use its own on-premises CUBE for PSTN connectivity while using Webex Calling for call control. It enables Webex Calling to send PSTN-bound calls to the on-premises CUBE, which then routes them to the PSTN. This preserves existing gateway investments and is a supported deployment option in Webex Control Hub.

Answer

Cisco Unified Communications Manager (CUCM) SIP trunk directly to Webex Calling

Answer

Cisco Expressway-E and Expressway-C pair for Mobile and Remote Access (MRA)

Answer

Webex Calling PSTN calling plan from Cisco

Question 2

An engineer is troubleshooting one-way audio for calls traversing a Cisco IOS XE router with NAT between an internal CUCM cluster and an external SIP provider. Signaling completes, but RTP from the provider never reaches the internal phone. The engineer confirms the provider is sending media to the signaling address. Which technology should be enabled on the router to allow the correct media address to be signaled to the provider?

Accepted Answer

Application Layer Gateway for SIP. When SIP signaling crosses a NAT boundary, the SDP body often carries a private IP address that the far end cannot reach, producing signaling success but one-way or no audio. A SIP Application Layer Gateway on the Cisco IOS XE router inspects the SDP and rewrites the connection and media attributes to the translated public address, so the provider sends RTP to the correct destination and audio flows in both directions.

Answer

Media Termination Point

Answer

SIP Normalization and Transparency

Answer

RSVP

Question 3

Which DSCP value is recommended for Call Signaling traffic in a Cisco Unified Communications network?

Accepted Answer

CS3 (24). Cisco recommends DSCP CS3 (24) for call signaling traffic in a Unified Communications network, which includes SCCP, SIP, and H.323 signaling between endpoints and call control. CS3 provides a distinct per-hop behavior from voice bearer traffic, which uses EF (46). This separation lets QoS policies prioritize voice media above signaling while still protecting signaling from best-effort traffic.

Answer

AF31 (26)

Answer

EF (46)

Answer

AF41 (34)

Question 4

Which TWO of the following are valid methods to handle digit manipulation in CUCM?

Accepted Answer

Translation Pattern. Translation Pattern (C) is a valid digit-manipulation method in CUCM because it matches a dialed digit string in a partition and applies transformations such as discarding digits (Discard Digits), prefixing digits, or rewriting the called/calling number before the call is routed. Calling Party Transformation Pattern (E) is also valid because it specifically manipulates the calling-party number (and related presentation settings) on inbound or outbound calls by matching the calling number and applying prefix, strip, or transformation masks. Route Filter (A) is not a digit-manipulation tool; it is used with route lists and time schedules to filter which route groups or dial peers can be selected based on dial-peer tags, not to rewrite digits. Region Matrix (B) governs codec selection between regions for calls, not digit manipulation. Location Configuration (D) is used for call admission control and bandwidth allocation between locations, not for altering dialed digits.

Answer

Route Filter

Answer

Region Matrix

Answer

Location Configuration

Question 5

A network administrator is troubleshooting poor voice quality on a Cisco Unified Communications Manager cluster. The administrator suspects that the issue is related to the Differentiated Services Code Point (DSCP) value being used for voice bearer traffic. Which DSCP value is recommended by Cisco for voice bearer traffic to ensure it receives priority treatment in the network?

Accepted Answer

EF (Expedited Forwarding). Cisco recommends marking voice bearer traffic with EF (Expedited Forwarding), which is DSCP 46. This marking ensures that voice packets are placed in a low-latency queue and receive priority treatment across the network. Other DSCP values like AF31, CS3, and AF41 are used for different traffic types such as call signaling and video, and do not provide the strict priority required for voice.

Answer

CS3 (Class Selector 3)

Answer

AF41 (Assured Forwarding 41)

Answer

AF31 (Assured Forwarding 31)

Question 6

You are managing a Cisco Collaboration cluster and notice that database replication is stuck in a '3' (blocked) state. What is the standard troubleshooting step?

Accepted Answer

utils dbreplication reset. When database replication is stuck in a '3' (blocked) state in a Cisco Collaboration cluster, the standard troubleshooting step is to run 'utils dbreplication reset' on the publisher or affected subscriber. This command resets the replication and forces a full re-sync of the database, resolving blocked states caused by inconsistencies or network issues.

Answer

utils service restart Cisco Database Layer Monitor

Answer

utils system restart

Answer

utils network ping

Question 7

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.. The best practice is to use a trusted third-party Certificate Authority (CA) for all servers in a CUCM and Expressway cluster. Public CA-signed certificates are trusted by default on endpoints, browsers, and other servers, eliminating the need to distribute and manually trust self-signed or internal CA certificates. This is especially critical for Expressway-E, which faces external endpoints that will not trust an internal CA.

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 8

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

Accepted Answer

Publisher. The Publisher node in a CUCM cluster is the only node that owns the master database and is responsible for all configuration changes. Subscribers receive replicated copies of the database and are read-only for configuration purposes.

Answer

Subscriber

Answer

TFTP node

Answer

Music on Hold (MoH) node

Question 9

In a Webex hybrid environment, what is the primary role of the Expressway-C?

Accepted Answer

To provide a secure connector for Hybrid Services. Expressway-C is deployed inside the enterprise network and acts as the secure connector that initiates outbound-only connections to Expressway-E, which then relays traffic to Webex cloud services. This connector role is what enables Hybrid Services (Calendar, Message, Directory, Management, Call) to traverse the firewall without inbound pinholes. It does not manage DNS or replace CUCM; it is purely a traversal/connector component in the hybrid architecture.

Answer

To manage public DNS records

Answer

To act as a SIP proxy for internal phones

Answer

To replace the CUCM server

Question 10

Which Cisco feature is used to ensure voice traffic is prioritized over web traffic on a Cisco access switch?

Accepted Answer

Quality of Service (QoS). Quality of Service (QoS) is the Cisco feature set used to classify, mark, and prioritize voice traffic over less delay-sensitive traffic like web browsing on an access switch. QoS mechanisms such as classification, marking (DSCP EF for voice), queuing, and policing ensure voice packets are forwarded with low latency and jitter. This is the standard answer for prioritizing voice over data on a Cisco access switch.

Answer

SNMP Traps

Answer

Spanning Tree Protocol

Answer

VLAN Trunking