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Intermediate Practice Exam
Question 1. Which Poly component acts as the central point for media mixing and transcoding in a large‑scale deployment? A) Poly Clariti Edge B) Poly Clariti Core C) RealPresence Collaboration Server (RMX) D) Poly Clariti Manager Answer: C Explanation: The Collaboration Server (RMX) provides MCU functions, mixing and transcoding audio/video streams for conferences. Question 2. In a Poly Clariti architecture, the Edge primarily performs which function? A) User authentication against LDAP B) License enforcement for endpoints C) Firewall/NAT traversal and SBC duties D) Generation of call detail records (CDR) Answer: C Explanation: The Edge sits at the network perimeter, handling SBC tasks such as protocol normalization and media relay for external traffic. Question 3. Which signaling protocol is NOT natively supported by Poly UC infrastructure? A) SIP B) H. C) MGCP D) WebRTC Answer: C
Intermediate Practice Exam
Explanation: MGCP is a media gateway control protocol and is not directly supported; Poly devices use SIP, H.323, or WebRTC for signaling. Question 4. When configuring QoS for video traffic, which DSCP value is recommended for high‑priority video streams? A) 0x08 (CS1) B) 0x28 (AF41) C) 0x2E (EF) D) 0x10 (AF21) Answer: C Explanation: EF (Expedited Forwarding) with DSCP 46 (0x2E) is standard for latency‑sensitive video to ensure minimal delay. Question 5. A Poly Clariti Core is licensed per: A) Number of concurrent calls B) Number of registered endpoints C) Number of CPU cores installed D) Number of virtual meeting rooms (VMR) created Answer: B Explanation: Licensing for Core is based on the count of registered Poly endpoints, not call concurrency or CPU. Question 6. Which protocol combination is used by Poly Clariti Edge to traverse NAT for SIP signaling? A) H.460.18 / H.460. B) STUN only
Intermediate Practice Exam
Question 9. To ensure time synchronization across all Poly components, which service should be configured? A) SNMP B) NTP C) DHCP D) LDAP Answer: B Explanation: Network Time Protocol (NTP) keeps clocks aligned, which is critical for certificate validity and logging. Question 10. When bulk provisioning Poly Group Series devices, which method is most efficient? A) Manually entering each device’s MAC address in the UI B) Importing a CSV file through Clariti Manager C) Using SSH to each device individually D) Configuring each device via its web UI Answer: B Explanation: Clariti Manager supports CSV import for bulk device provisioning, saving time compared to manual entry. Question 11. Which Poly endpoint firmware management best practice minimizes service disruption? A) Upgrade all devices simultaneously at peak hours B) Stagger upgrades and use “maintenance window” scheduling C) Disable all QoS settings before upgrade D) Upgrade only the Core firmware, not endpoints
Intermediate Practice Exam
Answer: B Explanation: Staggered upgrades during low‑usage windows reduce the impact on users and prevent simultaneous failures. Question 12. Which log type is most useful for diagnosing a one‑way audio problem in a conference? A) System boot logs B) License audit logs C) Call Detail Records (CDR) D) User authentication logs Answer: C Explanation: CDRs contain timestamps, codec negotiation, and media path information that help pinpoint audio issues. Question 13. In a Poly VMR configuration, the “Passcode Required” option primarily protects against: A) Unauthorized media streaming B) Unencrypted SIP signaling C) Unwanted participants joining the meeting D) License over‑use Answer: C Explanation: Requiring a passcode prevents unknown users from entering the virtual meeting room. Question 14. Which video layout automatically switches the active speaker’s video to the main screen?
Intermediate Practice Exam
Explanation: H.460.19 defines media relay functionality for cases where direct media cannot be established. Question 17. When configuring a firewall for Poly Clariti Core, which ports must be opened for SIP signaling? A) TCP 443 only B) UDP 5060 and TCP 5060 C) UDP 3478 only D) TCP 80 and 443 Answer: B Explanation: SIP commonly uses UDP/TCP 5060; both should be allowed for inbound/outbound signaling. Question 18. Which DSCP marking is appropriate for voice traffic to ensure low latency? A) 0x28 (AF41) B) 0x2E (EF) C) 0x10 (AF21) D) 0x08 (CS1) Answer: B Explanation: EF (Expedited Forwarding) is the standard DSCP for voice, providing priority handling. Question 19. In Poly Clariti Manager, the “Health Dashboard” primarily monitors which of the following? A) License expiration dates B) CPU, memory, and bandwidth utilization of Core/Edge nodes
Intermediate Practice Exam
C) User password complexity D. Number of LDAP groups Answer: B Explanation: The Health Dashboard gives real‑time metrics on resource consumption for core components. Question 20. Which certificate type is required on the Poly Clariti Edge to enable TLS for SIP signaling? A. Self‑signed client certificate B. Server certificate with a trusted CA chain C. Code‑signing certificate D. Wildcard certificate for all subdomains Answer: B Explanation: A server certificate signed by a trusted Certificate Authority enables TLS handshake for SIP. Question 21. Which of the following best describes the role of H.323 Gateways in a Poly deployment? A. Convert SIP to H.323 for legacy devices B. Provide DNS resolution for endpoints C. Manage user authentication against AD D. Perform media transcoding only Answer: A Explanation: H.323 Gateways translate SIP signaling to H.323, allowing interoperability with older equipment.
Intermediate Practice Exam
Explanation: ICE (Interactive Connectivity Establishment) discovers the best path for media across NAT/firewalls. Question 25. Which of the following is NOT a typical cause of “one‑way video” in a Poly conference? A. Mismatched video codecs between endpoints B. Firewall blocking RTP ports for the receiving side C. Incorrect DSCP marking on outbound video traffic D. Missing TLS certificate on the Core Answer: D Explanation: TLS certificates affect signaling encryption, not video flow; the other options directly impact video transport. Question 26. Poly Clariti Edge can be deployed in which of the following modes? A. Virtual Machine only B. Hardware appliance only C. Both virtual and hardware form factors D. Cloud‑only SaaS Answer: C Explanation: Edge is available as a virtual appliance and as a dedicated hardware box. Question 27. Which LDAP attribute is typically used by Clariti Manager to map a Poly user’s email address? A. cn B. mail C. uid
Intermediate Practice Exam
D. sn Answer: B Explanation: The “mail” attribute stores the user’s email address, which is used for notifications and identification. Question 28. When a Poly endpoint registers with Clariti Core, which protocol is used for the registration process? A. DHCP B. SNMP C. SIP REGISTER D. HTTP POST Answer: C Explanation: SIP REGISTER messages are used by endpoints to announce their presence to the Core. Question 29. Which of the following best describes “continuous presence” video layout? A. Only the active speaker’s video is shown B. All participants are displayed simultaneously in a tiled view C. A single speaker is shown while others are hidden D. Video is turned off for all but the host Answer: B Explanation: Continuous presence shows all video streams at once, typically in a grid. Question 30. In a Poly environment, which log level should be enabled for detailed troubleshooting of SIP signaling failures? A. INFO
Intermediate Practice Exam
A. Add more licenses before adding hardware B. Deploy additional Core nodes and enable load balancing C. Increase the size of the existing VM only D. Disable QoS to free resources Answer: B Explanation: Adding Core nodes and configuring load balancing distributes call load and improves resilience. Question 34. In a call flow that includes an external PSTN gateway, which protocol is typically used between the Poly Core and the gateway? A. SIP over TLS B. H.323 over TCP C. MGCP D. SCCP Answer: A Explanation: SIP over TLS provides secure signaling between the Core and PSTN gateways. Question 35. Which of the following statements about Poly Clariti Edge’s “media bypass” feature is correct? A. It forces all media to flow through the Edge regardless of network conditions. B. It allows direct media flow between internal endpoints when possible. C. It disables SRTP for all calls. D. It encrypts media with a proprietary algorithm. Answer: B Explanation: Media bypass enables direct media paths between internal devices, reducing latency and load on the Edge.
Intermediate Practice Exam
Question 36. Which of the following is the correct order of steps for restoring a Poly Clariti Manager backup? A. Install OS → Restore database → Import configuration files → Restart services B. Restore database → Install OS → Import configuration → Start services C. Import configuration → Restore database → Install OS → Restart services D. Install OS → Start services → Restore database → Import configuration Answer: A Explanation: The OS must be ready first, then the database is restored, followed by configuration files, and finally services are restarted. Question 37. What is the primary purpose of the “Call Admission Control” (CAC) feature in Poly infrastructure? A. Limit the number of concurrent users per LDAP group B. Prevent oversubscription of bandwidth by rejecting new calls when capacity is exceeded C. Enforce license compliance D. Automatically upgrade firmware on busy devices Answer: B Explanation: CAC monitors available resources and blocks additional calls when bandwidth or media resources are insufficient. Question 38. Which of the following NAT traversal techniques is most suitable for a corporate network that blocks UDP traffic? A. STUN only B. TURN relay over TCP C. ICE with UDP only
Intermediate Practice Exam
B. Only the designated host C. No one; video is disabled D. Only external guests Answer: B Explanation: Host‑only mode restricts video sharing to the host, preventing others from sending video. Question 42. Which of the following is the most accurate method to calculate required bandwidth for a mixed voice/video conference with 5 participants, each using 640 kbps video and 100 kbps audio? A. (5 × 640) + (5 × 100) = 3.7 Mbps B. (5 × 640) = 3.2 Mbps only C. (5 × 100) = 0.5 Mbps only D. (5 × 640) + (5 × 100) × 2 = 7.4 Mbps (double for uplink/downlink) Answer: A Explanation: Add video and audio per participant; total = 3.2 Mbps + 0.5 Mbps = 3.7 Mbps. Full‑duplex is assumed in the link capacity. Question 43. Which protocol is used by Poly Clariti Manager to push firmware updates to devices? A. TFTP B. HTTP/HTTPS C. FTP D. SNMP Answer: B Explanation: Firmware is delivered via secure HTTPS to ensure integrity and confidentiality.
Intermediate Practice Exam
Question 44. Which of the following security mechanisms protects Poly signaling traffic from man‑in‑the‑middle attacks? A. SRTP B. TLS C. STUN D. QoS Answer: B Explanation: TLS encrypts SIP/H.323 signaling, preventing interception and tampering. Question 45. In a Poly deployment, the “Resource Pool” configuration on the Collaboration Server is used to: A. Store user credentials B. Define limits for simultaneous video streams and ports C. Manage DNS records for endpoints D. Allocate storage for call recordings Answer: B Explanation: Resource pools set the maximum number of concurrent audio/video ports and define video resolution limits. Question 46. Which of the following is a key indicator of a mis‑configured firewall that would cause “media not received” errors? A. SIP 200 OK received but no RTP packets observed in capture B. DNS lookup failures for endpoint hostnames C. LDAP bind errors in Clariti Manager D. License server unreachable messages
Intermediate Practice Exam
B. Poly G7500 (Group Series) C. Poly Trio 8800 D. Poly VVX 601 Answer: B Explanation: The G7500 supports 1080p/4K video and thus uses the highest resolution settings. Question 50. In the context of Poly infrastructure, “license pooling” allows: A. Sharing a single license across multiple cores simultaneously B. Dynamically assigning licenses to devices as they register C. Extending license validity indefinitely D. Using a license for both audio and video simultaneously Answer: B Explanation: License pooling enables the system to allocate licenses on‑demand to registered devices. Question 51. Which of the following is the correct order of operations for a typical external SIP call entering a Poly Clariti Edge? A. NAT traversal → TLS handshake → SIP INVITE → Media negotiation B. TLS handshake → NAT traversal → SIP INVITE → Media negotiation C. SIP INVITE → TLS handshake → NAT traversal → Media negotiation D. Media negotiation → SIP INVITE → TLS handshake → NAT traversal Answer: B Explanation: The Edge first establishes a TLS-secured signaling channel, then handles NAT traversal before processing the INVITE and media.
Intermediate Practice Exam
Question 52. Which of the following is NOT a function of the Poly Clariti Manager’s “Alert Engine”? A. Trigger email notifications on high CPU usage B. Automatically increase licensed endpoint count C. Generate SNMP traps for critical events D. Log warning messages for failed device registrations Answer: B Explanation: The Alert Engine notifies; it does not modify license counts automatically. Question 53. When configuring a Poly VMR for “anonymous join”, what security risk is introduced? A. Unencrypted media streams B. Potential for uninvited participants to join meetings C. License over‑usage D. Loss of DSCP markings Answer: B Explanation: Allowing anonymous join removes the need for authentication, increasing the chance of unwanted attendees. Question 54. Which of the following best describes the purpose of “media transcoding” on a Poly Collaboration Server? A. Converting audio codecs only B. Adjusting video resolution to match endpoint capabilities C. Encrypting media streams D. Performing NAT traversal Answer: B
