1
3CX Academy Advanced Certification Exam
Actual Exam 2026/2027 | Complete Exam-Style
Questions | 100% Verified – Detailed Rationales –
Pass Guaranteed – A+ Graded
TABLE OF CONTENTS
Section 1 | 3CX Architecture and Deployment | Q1 – Q10
Section 2 | User Configuration and Extension Management | Q11 – Q20
Section 3 | SIP Trunking and Advanced Routing | Q21 – Q30
Section 4 | Security, Monitoring, and Troubleshooting | Q31 – Q40
Section 5 | System Backup, Updates, and Disaster Recovery | Q41 – Q50
Instructions: Choose the single best answer. Pass: 80% in 90 minutes.
══════════════════════════════════════
SECTION 1: 3CX ARCHITECTURE AND DEPLOYMENT Q1 – Q10
════════════════════════════════════════
Question 1 of 50
You are designing a High Availability (HA) architecture for a remote office with 50 users using
the 3CX Edge device. The local internet connection is unstable, so you need to ensure
survivability for local extensions. Which deployment model provides local survivability without
requiring a constant VPN tunnel back to the core data center?
A. Cloud-only deployment with softphones
B. Local Edge Gateway in Media Mode
C. Local Edge Gateway in Registration Mode
D. Standard SIP phones without an Edge Gateway
Correct Answer: C
,2
Rationale: In Registration Mode, the Edge Gateway registers locally with the core but can
process calls locally if the WAN link fails, ensuring essential services remain active. Media
Mode processes media locally but requires the signaling path to remain available over the WAN,
which defeats the purpose of unstable connectivity survivability.
Question 2 of 50
A client reports that calls are cutting in and out when multiple users are on conference calls. You
check the router and notice the QoS markings are set to DSCP 0. The codec in use is G.711.
Which bandwidth calculation should you use to determine the minimum bandwidth per
concurrent call?
A. 24 Kbps
B. 64 Kbps
C. 87 Kbps
D. 120 Kbps
Correct Answer: C
Rationale: The standard calculation for G.711 (64 kbps payload) plus IP/UDP/RTP headers
(typically 20-25 kbps) results in approximately 87 kbps per call. Using 64 kbps ignores the
overhead, leading to congestion when multiple calls share the link.
Question 3 of 50
You are configuring the firewall for a new 3CX SBC (Session Border Controller) deployment.
The SBC must communicate with external SIP trunks via UDP 5060. However, you also need to
allow TLS signaling for secure remote worker connections. Which ports must be open on the
external firewall?
A. UDP 5060 and TCP 5061 only
B. UDP 5060 and TCP 443
C. TCP 5061 only
D. UDP 5060, TCP 5061, and TCP 443
, 3
Correct Answer: D
Rationale: While UDP 5060 and TCP 5061 handle standard SIP signaling, the 3CX WebRTC and
softphone clients typically use TCP 443 for HTTPS/TLS signaling to traverse firewalls easily.
Restricting to only SIP ports would block remote softphone registration.
Question 4 of 50
During the initial system health check, you observe that the 3CX application servers show high
CPU utilization. Upon investigation, you see the "Transcoding" service is consuming the most
resources. Which configuration change would most effectively reduce this load?
A. Increasing the RAM on the virtual machine
B. Disabling call recording globally
C. Forcing all endpoints to use the same codec (e.g., G.711)
D. Enabling G.729a compression
Correct Answer: C
Rationale: Transcoding consumes significant CPU resources when converting between different
codecs (e.g., G.711 to G.729). Standardizing the codec across all devices eliminates the need for
the system to convert audio streams in real-time. Enabling G.729a (Option D) actually increases
processing power compared to G.711 due to compression complexity.
Question 5 of 50
A branch office has migrated to the 3CX platform, but users report that inbound calls are failing
while outbound calls work fine. You verify that the DID range is routed to the correct Trunk.
Which SIP 503 response code indicates that the server cannot locate the user?
A. 200 OK
B. 403 Forbidden
C. 404 Not Found
3CX Academy Advanced Certification Exam
Actual Exam 2026/2027 | Complete Exam-Style
Questions | 100% Verified – Detailed Rationales –
Pass Guaranteed – A+ Graded
TABLE OF CONTENTS
Section 1 | 3CX Architecture and Deployment | Q1 – Q10
Section 2 | User Configuration and Extension Management | Q11 – Q20
Section 3 | SIP Trunking and Advanced Routing | Q21 – Q30
Section 4 | Security, Monitoring, and Troubleshooting | Q31 – Q40
Section 5 | System Backup, Updates, and Disaster Recovery | Q41 – Q50
Instructions: Choose the single best answer. Pass: 80% in 90 minutes.
══════════════════════════════════════
SECTION 1: 3CX ARCHITECTURE AND DEPLOYMENT Q1 – Q10
════════════════════════════════════════
Question 1 of 50
You are designing a High Availability (HA) architecture for a remote office with 50 users using
the 3CX Edge device. The local internet connection is unstable, so you need to ensure
survivability for local extensions. Which deployment model provides local survivability without
requiring a constant VPN tunnel back to the core data center?
A. Cloud-only deployment with softphones
B. Local Edge Gateway in Media Mode
C. Local Edge Gateway in Registration Mode
D. Standard SIP phones without an Edge Gateway
Correct Answer: C
,2
Rationale: In Registration Mode, the Edge Gateway registers locally with the core but can
process calls locally if the WAN link fails, ensuring essential services remain active. Media
Mode processes media locally but requires the signaling path to remain available over the WAN,
which defeats the purpose of unstable connectivity survivability.
Question 2 of 50
A client reports that calls are cutting in and out when multiple users are on conference calls. You
check the router and notice the QoS markings are set to DSCP 0. The codec in use is G.711.
Which bandwidth calculation should you use to determine the minimum bandwidth per
concurrent call?
A. 24 Kbps
B. 64 Kbps
C. 87 Kbps
D. 120 Kbps
Correct Answer: C
Rationale: The standard calculation for G.711 (64 kbps payload) plus IP/UDP/RTP headers
(typically 20-25 kbps) results in approximately 87 kbps per call. Using 64 kbps ignores the
overhead, leading to congestion when multiple calls share the link.
Question 3 of 50
You are configuring the firewall for a new 3CX SBC (Session Border Controller) deployment.
The SBC must communicate with external SIP trunks via UDP 5060. However, you also need to
allow TLS signaling for secure remote worker connections. Which ports must be open on the
external firewall?
A. UDP 5060 and TCP 5061 only
B. UDP 5060 and TCP 443
C. TCP 5061 only
D. UDP 5060, TCP 5061, and TCP 443
, 3
Correct Answer: D
Rationale: While UDP 5060 and TCP 5061 handle standard SIP signaling, the 3CX WebRTC and
softphone clients typically use TCP 443 for HTTPS/TLS signaling to traverse firewalls easily.
Restricting to only SIP ports would block remote softphone registration.
Question 4 of 50
During the initial system health check, you observe that the 3CX application servers show high
CPU utilization. Upon investigation, you see the "Transcoding" service is consuming the most
resources. Which configuration change would most effectively reduce this load?
A. Increasing the RAM on the virtual machine
B. Disabling call recording globally
C. Forcing all endpoints to use the same codec (e.g., G.711)
D. Enabling G.729a compression
Correct Answer: C
Rationale: Transcoding consumes significant CPU resources when converting between different
codecs (e.g., G.711 to G.729). Standardizing the codec across all devices eliminates the need for
the system to convert audio streams in real-time. Enabling G.729a (Option D) actually increases
processing power compared to G.711 due to compression complexity.
Question 5 of 50
A branch office has migrated to the 3CX platform, but users report that inbound calls are failing
while outbound calls work fine. You verify that the DID range is routed to the correct Trunk.
Which SIP 503 response code indicates that the server cannot locate the user?
A. 200 OK
B. 403 Forbidden
C. 404 Not Found
