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Cisco 350-801 CLCOR practice questions

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Question 1Infrastructure and Design

In a Cisco Unified Communications Manager cluster, which node is installed first and acts as the authoritative source for database replication?

  1. The publisher node Correct answer.
  2. The subscriber node
  3. The media resource node
  4. The TFTP server node

Explanation

The first node installed in a cluster is the publisher. It holds the master database, and subscribers replicate their databases from it.

Question 2Infrastructure and Design

Which device pool setting defines the codec that is used for calls between devices assigned to that device pool?

  1. Location
  2. Network locale
  3. Region Correct answer.
  4. Date/time group

Explanation

The region assigned to a device pool determines which codecs are allowed between devices in that region and other regions. The location setting controls bandwidth, not codec selection.

Question 3Infrastructure and Design

Two sites are limited to 512 kbps of WAN bandwidth for voice. Which CUCM feature enforces the maximum number of calls allowed between the sites?

  1. Device pools
  2. Regions
  3. Locations Correct answer.
  4. Media resource group lists

Explanation

Locations implement call admission control by limiting the bandwidth available between locations. When the limit is reached, further calls are denied or rerouted.

Question 4Infrastructure and Design

A phone's calling search space contains only partition A. A user dials a number that exists only as a route pattern in partition B. What is the result?

  1. The call uses the phone's secondary calling search space.
  2. The call is rejected because no dialed number matches in the phone's search space. Correct answer.
  3. The call matches and is routed through partition B.
  4. The call matches because route patterns are global.

Explanation

A calling search space is an ordered list of partitions that the device can search. If the dialed number resides in a partition that is not in the CSS, CUCM has no matching pattern and rejects the call.

Question 5Infrastructure and Design

Which dial plan element can manipulate digits before a route pattern is matched and does not route the call itself?

  1. Hunt pilot
  2. Route list
  3. Translation pattern Correct answer.
  4. Route pattern

Explanation

A translation pattern transforms the called number and then returns the call to the dial plan for further matching. It does not select a destination or route the call directly.

Question 6Infrastructure and Design

What is the purpose of an SRST reference in a device pool?

  1. It allows branch phones to fall back to a local gateway for call control when the WAN to CUCM is down. Correct answer.
  2. It provides a secondary TFTP server for phone firmware.
  3. It lists the media resources available at the branch.
  4. It defines the codec used between branch phones.

Explanation

SRST lets a local router provide limited call control for branch phones if they lose connectivity to the CUCM cluster. The SRST reference in the device pool tells the phones which gateway to use.

Question 7Infrastructure and Design

Which SIP trunk setting specifies the IP address or DNS name to which CUCM sends calls over the trunk?

  1. SIP profile
  2. Device pool
  3. Route group
  4. Destination address Correct answer.

Explanation

The SIP trunk destination address defines the remote peer for the trunk. CUCM sends SIP requests to that address for calls routed over the trunk.

Question 8Infrastructure and Design

Which media resource provides a media termination point for functions such as DTMF conversion or holding media streams?

  1. Media termination point Correct answer.
  2. Music on hold server
  3. Conference bridge
  4. Transcoder

Explanation

A media termination point (MTP) terminates and relays media streams. It is used for DTMF conversion, early media, and other anchoring needs.

Question 9Infrastructure and Design

A branch phone using G.729 calls a conference bridge that supports only G.711. Which resource must CUCM allocate?

  1. Route group
  2. Media termination point
  3. Music on hold server
  4. Transcoder Correct answer.

Explanation

A transcoder converts the G.729 stream to G.711 so the conference bridge can process it. Without a transcoder, the codec mismatch prevents the call from completing.

Question 10Infrastructure and Design

Which music on hold configuration lets many phones receive a single audio stream and reduces WAN bandwidth usage?

  1. Multicast MOH using a route group
  2. Multicast MOH using a multicast address Correct answer.
  3. Unicast MOH with a transcoder
  4. Unicast MOH with a dedicated server per site

Explanation

Multicast MOH sends one stream to a multicast group address that multiple phones can join. This reduces the number of individual streams across the WAN.

Question 11Infrastructure and Design

Which DHCP option carries a list of TFTP server IP addresses to Cisco IP phones?

  1. Option 43
  2. Option 150 Correct answer.
  3. Option 66
  4. Option 3

Explanation

Cisco IP phones use DHCP option 150 to learn one or more TFTP server IP addresses. Option 66 carries a single TFTP server name rather than an IP address list.

Question 12Infrastructure and Design

Which service on a CUCM node serves phone configuration files and firmware to endpoints?

  1. Cisco CTIManager
  2. Cisco CallManager
  3. Cisco TFTP Correct answer.
  4. Cisco RIS Data Collector

Explanation

The Cisco TFTP service builds and serves configuration files and firmware files to phones. Phones learn the TFTP address through DHCP.

Question 13Infrastructure and Design

Which statement describes LDAP synchronization in CUCM?

  1. It replaces the dial plan with directory numbers from LDAP.
  2. It stores user passwords in the CUCM database for local authentication.
  3. It imports user records from the directory, while authentication can be performed against the LDAP server. Correct answer.
  4. It creates device profiles for each imported user automatically.

Explanation

LDAP synchronization imports user data such as names and telephone numbers into CUCM. When LDAP authentication is enabled, credentials are verified against the external directory rather than a local password.

Question 14Infrastructure and Design

Which certificate does a CUCM cluster present to a remote SIP peer for a TLS-secured SIP trunk?

  1. CAPF certificate
  2. Tomcat certificate
  3. IPsec certificate
  4. CallManager certificate Correct answer.

Explanation

SIP TLS uses the CallManager certificate, which is the certificate associated with the CallManager service. The peer must trust this certificate to complete the TLS handshake.

Question 15Infrastructure and Design

Which configuration determines the order of CUCM nodes to which a phone attempts to register?

  1. CUCM group Correct answer.
  2. SIP profile
  3. Region
  4. Device pool

Explanation

A CUCM group is an ordered list of CUCM nodes assigned through the device pool. Phones try the nodes in order, providing redundancy if the primary is unavailable.

Question 16Infrastructure and Design

Which statement about deploying CUCM on virtualization is correct?

  1. Any hypervisor and hardware combination may be used if performance is adequate.
  2. Cisco-provided OVA templates and supported hardware must be used for the VM. Correct answer.
  3. CUCM requires a physical server for the publisher and a VM for subscribers.
  4. CPU and memory settings can be reduced to save resources as long as the VM boots.

Explanation

Cisco supports CUCM virtualization only on tested hardware and with the Cisco-provided OVA template. Changing CPU or memory settings outside the OVA is not supported.

Question 17Infrastructure and Design

Which licensing model is used by CUCM 12.5 and later?

  1. Per-phone paper licenses
  2. Concurrent user licenses
  3. Smart Software Licensing Correct answer.
  4. Node-locked MAC address licenses

Explanation

CUCM 12.5 uses Cisco Smart Software Licensing, which registers with a smart account or satellite for license consumption and reporting.

Question 18Infrastructure and Design

A route list contains route group A (order 1) and route group B (order 2). How does CUCM select a route group for a call?

  1. It uses the route group with the most available channels.
  2. It load-balances across all route groups equally.
  3. It tries route group A first and falls to route group B only if A is unavailable. Correct answer.
  4. It selects route group B first because it is the backup.

Explanation

A route list evaluates route groups in the configured order. The first route group with an available destination is used; later groups serve as fallback.

Question 19Infrastructure and Design

Which feature distributes incoming calls to a defined group of users in a specified order?

  1. Hunt group Correct answer.
  2. Translation pattern
  3. Call pickup
  4. Call park

Explanation

A hunt group uses a hunt pilot and line members to route calls to available users according to the hunt algorithm. It is used for department or support queues.

Question 20Infrastructure and Design

Which feature lets a user log in to a shared phone and receive their own directory number and settings?

  1. Extension Mobility Correct answer.
  2. Cisco Unified Mobility
  3. Device mobility
  4. SRST

Explanation

Cisco Extension Mobility allows a user to authenticate to a phone and download a personal device profile. The phone then uses the user's lines and settings.

Question 21Infrastructure and Design

Which feature changes a phone's device pool, calling search space, and region based on the IP subnet where it registers?

  1. Device Mobility Correct answer.
  2. Region
  3. Extension Mobility
  4. Location

Explanation

Device Mobility uses device mobility groups and IP subnets to apply location-specific settings to a phone when it roams. This keeps dialing and bandwidth policy appropriate for the visited site.

Question 22Infrastructure and Design

In a SAML SSO deployment for CUCM, which component authenticates the user's credentials?

  1. The CUCM TFTP server
  2. The identity provider Correct answer.
  3. Cisco IM and Presence
  4. The CUCM publisher

Explanation

With SAML SSO, CUCM redirects the user to an identity provider for authentication. The IdP validates credentials and returns a signed assertion that CUCM trusts.

Question 23Infrastructure and Design

Which Cisco collaboration component provides presence and instant messaging in an on-premises deployment?

  1. Cisco IM and Presence Service Correct answer.
  2. Cisco Expressway
  3. Cisco Unity Connection
  4. Cisco Unified Communications Manager

Explanation

Cisco IM and Presence Service supplies presence status and instant messaging for Jabber and other clients. It integrates with CUCM for user and contact data.

Question 24Infrastructure and Design

Which gateway control protocol uses a call agent to control a media gateway and is commonly used to control PRI gateways?

  1. SCCP
  2. MGCP Correct answer.
  3. H.323
  4. SIP

Explanation

MGCP is a centralized gateway control protocol in which a call agent such as CUCM controls the gateway's endpoints. It is often used for PRI and analog gateway ports.

Question 25Infrastructure and Design

A location is configured with 512 kbps of available bandwidth, and each G.729 call consumes 24 kbps. What is the maximum number of G.729 calls that call admission control admits?

  1. 20
  2. 26
  3. 21 Correct answer.
  4. 24

Explanation

Divide the available bandwidth by the per-call bandwidth: 512 ÷ 24 = 21.33. CAC admits whole calls only, so the limit is 21 calls.

Question 26Infrastructure and Design

Which configuration object in Cisco Unified CM supplies default settings that apply to every phone in the cluster unless a more specific setting overrides them?

  1. A device pool, which groups devices that share region, location, and date/time settings for a site.
  2. A common phone profile, which applies a shared set of phone-specific settings to a group of devices.
  3. The enterprise phone configuration, which carries settings applied to every phone in the cluster. Correct answer.
  4. A phone button template, which defines the line and speed-dial layout used by a phone model.

Explanation

The enterprise phone configuration holds cluster-wide phone defaults, such as Do Not Disturb and background image settings, which Cisco Unified CM applies to all phones. Device pools, common phone profiles, and individual phone pages can override specific values, but the enterprise-level defaults apply wherever no override exists.

Question 27Infrastructure and Design

Which node in a Cisco Unified CM cluster is installed first and holds the master copy of the cluster database?

  1. The publisher, which is installed first and holds the master copy of the cluster database. Correct answer.
  2. The TFTP server, which hosts phone configuration files and firmware images for the cluster.
  3. The IM and Presence node, which stores the cluster's user directory information.
  4. A subscriber node that is designated as the primary call-processing server for the cluster.

Explanation

The first node installed in a cluster is the publisher; it owns the master database that all other nodes replicate from. Subscribers run call processing and receive database updates from the publisher rather than authoring them.

Question 28Infrastructure and Design

What is the function of the Cisco Unified CM Annunciator?

  1. It plays prerecorded announcements and tones to callers on behalf of Cisco Unified CM. Correct answer.
  2. It converts between codecs when two endpoints do not share a common codec.
  3. It provides music streams to callers who are placed on hold.
  4. It mixes multiple audio streams into a single conference call.

Explanation

The Annunciator is a media resource that plays announcements and tones, such as a reorder tone or a "number not in service" message, when no other resource can handle the call. It does not transcode, mix conferences, or supply hold music.

Question 29Infrastructure and Design

Which DSCP value does Cisco recommend for voice bearer traffic?

  1. EF (46) Correct answer.
  2. AF41 (34)
  3. CS3 (24)
  4. AF21 (18)

Explanation

Cisco's QoS baseline marks voice bearer (RTP) traffic with Expedited Forwarding, DSCP 46, which receives low-latency queuing treatment. Signaling, video, and call-center applications use lower classes such as CS3, AF41, and AF21.

Question 30Infrastructure and Design

A date/time group is assigned to a device pool. What does that setting control?

  1. The time zone offset and the date/time format that phones display. Correct answer.
  2. The timestamp format used in the call detail records written by the publisher.
  3. The NTP server that phones use to synchronize their internal clocks.
  4. The validity period of the certificate that phones use for secure registration.

Explanation

A date/time group defines the time zone and the display format of the date and time on phones that use it. It changes only what the phone shows and does not supply NTP, affect CDR content, or influence certificates.

Question 31Infrastructure and Design

A dial plan must convert the four-digit internal extension 1234 into +14085551234 before the call leaves the cluster, without sending the call to a destination. Which configuration accomplishes this?

  1. A route pattern that matches 1234 and applies a called-party transformation mask before routing.
  2. A translation pattern that matches 1234 and rewrites it with a called-party transformation mask. Correct answer.
  3. A hunt pilot that distributes the call to a group of directory numbers with a forward setting.
  4. The external phone number mask configured on the line of the calling phone.

Explanation

A translation pattern matches digits and rewrites them, then hands the call back for further analysis instead of delivering it to a destination. A route pattern also rewrites digits, but only while routing the call over a specific destination.

Question 32Infrastructure and Design

The route pattern 9.@ is placed in the partition PSTN. A phone's calling search space contains only the partition INTERNAL. What happens when the user dials 95551234?

  1. The call is routed after Cisco Unified CM automatically adds the missing partition to the calling search space.
  2. The call is routed because route patterns are matched regardless of the partitions in the calling search space.
  3. The call is completed using the phone's local dial plan without involving Cisco Unified CM.
  4. The call is rejected because no partition in the calling search space contains a matching pattern. Correct answer.

Explanation

A calling search space is an ordered collection of partitions, and Cisco Unified CM only considers patterns that live in those partitions. Because PSTN is not in the search space, no pattern can match and the call fails with a no-route condition.

Question 33Infrastructure and Design

A partition is configured with the urgent priority option. How does this affect digit analysis?

  1. Patterns in the urgent partition are checked first, even over a more specific match in a non-urgent partition. Correct answer.
  2. Calls that match the partition receive a higher QoS marking when they cross the WAN.
  3. The partition can no longer be included in more than one calling search space at a time.
  4. The partition is automatically moved to the end of every calling search space that contains it, so it is searched last.

Explanation

Urgent priority changes the normal best-match logic: any pattern in an urgent partition wins over patterns in non-urgent partitions, even if a non-urgent partition holds a longer, more specific match. It is commonly used so that emergency or special dialing strings cannot be shadowed by a shorter pattern.

Question 34Infrastructure and Design

An engineer enables SIP OPTIONS ping on a SIP trunk. What is the result of this configuration?

  1. OPTIONS messages are used to synchronize the trunk's dial plan with the remote peer.
  2. Cisco Unified CM sends periodic OPTIONS requests and stops using the trunk when no response is received. Correct answer.
  3. The trunk renegotiates its codec list every time an OPTIONS message is exchanged.
  4. Calls are placed on hold while the OPTIONS response from the far end is verified.

Explanation

With OPTIONS ping enabled, Cisco Unified CM periodically probes the destination and marks the trunk out of service if the peer stops responding. Calls then follow the next route group or route list member instead of failing on a dead trunk.

Question 35Infrastructure and Design

Which function does Cisco Unified Border Element provide at the edge of an enterprise collaboration network?

  1. It mixes audio streams and provides music on hold to callers waiting in a queue.
  2. It performs digit analysis and route list selection for calls between clusters.
  3. It terminates SIP signaling and media from the enterprise and re-originates them toward the service provider. Correct answer.
  4. It registers IP phones at the edge of the network and serves their configuration files and firmware across the cluster.

Explanation

Cisco Unified Border Element is a session border controller that terminates the enterprise side of a SIP trunk and builds a separate session toward the provider. This provides topology hiding, security, protocol interworking, and SIP normalization at the demarcation point.

Question 36Infrastructure and Design

What does a media resource group list control for a device?

  1. The order in which media resource groups are searched when Cisco Unified CM allocates a media resource. Correct answer.
  2. The maximum number of simultaneous conferences that each subscriber node in the cluster is allowed to host.
  3. The codec that each media resource uses when it is allocated to a call between two regions.
  4. The locations that are subject to call admission control for devices assigned to the list.

Explanation

A media resource group list defines the ordered set of media resource groups that a device may use, and Cisco Unified CM walks that order when it needs a conference bridge, MTP, transcoder, or music on hold server. Ordering the list lets administrators prefer local resources before resources across the WAN.

Question 37Infrastructure and Design

Which traffic type does Cisco recommend marking with DSCP CS3 (24)?

  1. Call signaling exchanged between endpoints and call control. Correct answer.
  2. Video conferencing media carried across the WAN between sites.
  3. Best-effort traffic from desktop PCs attached to IP phones.
  4. Voice bearer audio carried in Real-time Transport Protocol streams.

Explanation

Cisco's QoS baseline places call signaling, such as SIP, SCCP, H.323, and MGCP, in the CS3 class. Voice bearer uses EF, interactive video uses AF41, and PC data is normally marked as best effort or a low-priority data class.

Question 38Infrastructure and Design

Region A uses G.722 for calls within the region and Region B uses G.711 within its region. The region relationship between Region A and Region B is set to G.729. Two phones that support all three codecs, one in each region, place a call. Which codec carries the media?

  1. G.711, because it is the default codec used for all inter-region calls.
  2. No codec, because Cisco Unified CM allocates a transcoder and the call fails without one.
  3. G.729, because the codec configured for the relationship between the two regions applies. Correct answer.
  4. G.722, because it is the highest-quality codec that both phones support.

Explanation

Regions define the codec used within a region, and each pair of regions has its own relationship that defines the codec used between them. Because the A-to-B relationship is set to G.729, that codec is used for the call even though each phone supports higher-quality codecs.

Question 39Infrastructure and Design

Cisco IP phones with a PC port connect to Catalyst switch access ports, and the PCs behind the phones must not be able to inject marked traffic. Where and how should the QoS trust boundary be placed?

  1. Disable QoS on the port and let the WAN edge classify all traffic as best effort.
  2. Trust all traffic on the port unconditionally, because the phone re-marks the traffic it receives from the PC.
  3. Trust CoS on the voice VLAN and trust DSCP on the data VLAN by default.
  4. Configure the port to trust DSCP only when a Cisco phone is detected, so PC traffic stays untrusted. Correct answer.

Explanation

The trust boundary should sit at the switch port that faces the phone, with conditional trust so the port trusts DSCP only while a Cisco phone is detected. Traffic entering the PC port of the phone is then re-marked or policed rather than trusted, which preserves QoS markings end to end.

Question 40Infrastructure and Design

Which statement describes the role of a Cisco gatekeeper in an H.323 voice network?

  1. It converts SIP signaling from the service provider into SCCP for the IP phones.
  2. It terminates media streams and transcodes between dissimilar codecs at the edge of the network.
  3. It performs call admission control and address resolution for H.323 endpoints using RAS messages. Correct answer.
  4. It supplies DHCP and TFTP services so that IP phones can register with the call-processing cluster.

Explanation

A gatekeeper provides admission control, bandwidth management, and address resolution for H.323 endpoints and gateways by exchanging Registration, Admission, and Status messages. It controls signaling decisions but does not handle the media path itself.

Question 41Protocols and Codecs

Which SIP method is used to initiate a session and typically carries the initial SDP offer?

  1. ACK
  2. REGISTER
  3. INVITE Correct answer.
  4. OPTIONS

Explanation

The INVITE method starts a SIP dialog and normally carries the caller's SDP offer. The other methods register a contact, query capabilities, or acknowledge a final response.

Question 42Protocols and Codecs

Which SIP method terminates an established dialog?

  1. UPDATE
  2. BYE Correct answer.
  3. PRACK
  4. CANCEL

Explanation

BYE ends an established dialog and can be sent by either participant. CANCEL only stops a request that has not yet received a final response.

Question 43Protocols and Codecs

What is the primary function of SDP in a SIP session?

  1. It authenticates endpoints against the registrar
  2. It defines the path that SIP requests take through proxies
  3. It sets the DSCP value for the voice bearer
  4. It describes media streams, codecs, and transport addresses Correct answer.

Explanation

SDP is the session description carried in SIP bodies; it lists media types, codecs, ports, and connection addresses. SIP headers handle routing and authentication.

Question 44Protocols and Codecs

What is the payload bit rate of the G.711 codec?

  1. 128 kbps
  2. 16 kbps
  3. 64 kbps Correct answer.
  4. 8 kbps

Explanation

G.711 uses 8-bit PCM at 8 kHz sampling, producing a 64 kbps payload. It is the narrowband baseline codec.

Question 45Protocols and Codecs

What is the payload bit rate of the G.729 codec?

  1. 64 kbps
  2. 32 kbps
  3. 8 kbps Correct answer.
  4. 16 kbps

Explanation

G.729 uses CS-ACELP and compresses speech to 8 kbps, making it suitable for bandwidth-constrained links. G.711 uses 64 kbps.

Question 46Protocols and Codecs

What does SRTP provide for an RTP media stream?

  1. It encrypts and authenticates RTP media packets Correct answer.
  2. It translates between incompatible codecs
  3. It carries SIP signaling over TLS
  4. It compresses RTP headers across WAN links

Explanation

SRTP adds encryption, message authentication, and replay protection to RTP media. It does not compress headers or translate codecs.

Question 47Protocols and Codecs

Which mechanism sends DTMF digits as named telephone-event packets inside RTP?

  1. RFC 2833 telephone-event RTP packets Correct answer.
  2. In-band audio tones inside the voice codec
  3. KPML SUBSCRIBE and NOTIFY messages
  4. SIP INFO messages with a signal parameter

Explanation

RFC 2833, updated by RFC 4733, sends DTMF as named telephone-event packets inside RTP, so the tones are out-of-band but still in the media stream. In-band tones travel as audio, SIP INFO uses signaling, and KPML uses SUBSCRIBE/NOTIFY.

Question 48Protocols and Codecs

Which DSCP value is recommended for voice bearer traffic?

  1. EF (46) Correct answer.
  2. CS3 (24)
  3. AF31 (26)
  4. AF41 (34)

Explanation

EF, DSCP 46, is the expedited forwarding class used for voice bearer traffic to provide low latency, low jitter, and low loss. AF41 is used for interactive video.

Question 49Protocols and Codecs

A caller hears ringback but no early media is being sent. Which SIP provisional response indicates this condition?

  1. 183 Session Progress
  2. 100 Trying
  3. 180 Ringing Correct answer.
  4. 200 OK

Explanation

180 Ringing tells the caller the callee is alerting and does not itself carry early media. 183 Session Progress can include SDP so the caller can receive early media.

Question 50Protocols and Codecs

To which SIP response class does 302 Moved Temporarily belong?

  1. 2xx
  2. 3xx Correct answer.
  3. 1xx
  4. 4xx

Explanation

3xx responses are the redirection class, such as 301 Moved Permanently and 302 Moved Temporarily. 1xx is provisional, 2xx is success, and 4xx is request failure.