3CX ADVANCED CERTIFICATION EXAM 2023-2024 ACTUAL EXAM 100 QUESTIONS AND CORRECT
DETAILED ANSWERS
In the criteria of the "Outbound Rules", "Calls from Extension(s)" having comma separated values will
allow multiple extension ranges to be defined - (answer) True
The Virtual Extension of the slave must match the master side virtual extension number - (answer)
True
For extensions that are registered over multiple site-to-site VPNs, by default 3CX delivers the audio
between phones if they are on different subnets. - (answer) False
On outbound calls to external numbers, 3CX will process "Outbound Rules" in a "Best Matching" way,
depending on how many of the criteria match. - (answer) False
Wireshark can - without any additional Plugins Decode all Codecs including G711A, G711U, GSM, G729,
G726 - (answer) False
STUN extensions can be configured to connect to the tunnel port of 3CX instead of the SIP port for more
security. - (answer) False
The log files of 3CX are never cleaned even when you restart the 3CX Services - (answer) False
Once Secure SIP has been configured in 3CX, Secure SIP certificates will need to be deployed manually in
phones and softphones OS so that they can communicate. - (answer) False
Remote extensions may be provisioned using the HTTP or HTTPS URLs - (answer) False
The default Voicemail PIN of an extension consist of 4 random alphanumerical characters. - (answer)
False
Your 3CX has only one SIP Trunk and receives a call from number 8135791691. If you have a "Inbound
CID Reformatting" rule on the Trunk with "Source Pattern" 813(...)(.*) and "Replace Pattern" \1\2, the
extension that receives the call will see "5791691" as the caller ID on its display. - (answer) True
,3CX ADVANCED CERTIFICATION EXAM 2023-2024 ACTUAL EXAM 100 QUESTIONS AND CORRECT
DETAILED ANSWERS
When 3CX has been installed without a FQDN from 3CX and in split DNS mode, the DNS server must not
be installed on the same machine as the phone system. - (answer) True
Your Local IP Phone loses the registration to 3CX and you want do troubleshoot the issue. You should
start a Wireshark Capture on the 3CX Server, reboot the phone, and then apply the Filter
sip.Cseq.Method==REGISTER in order to see if registrations are reaching 3CX - (answer) True
Your 3CX has only one SIP Trunk and receives a call from number 422033272020 and you want it to be
presented on the extension display as +44272020. You can do this with a "Inbound CID Reformatting"
rule on the Trunk with "Source Pattern" 44(..)(..)(.*) and "Replace Pattern" +44\3. - (answer) True
When selecting the option "I need a 3CX FQDN" an internal DNS is not mandatory - (answer) True
The order of "Inbound Rules" is not important when you have DID and CID "Inbound Rules", CIDs always
have higher priority. - (answer) False
You have a Master Bridge with 3-digit extensions 1xxx and a Slave Bridge with 4-digit extensions 2xxx. In
the "Outbound Rules" you use to rote calls across the bridge, using a prefix is mandatory. - (answer)
False
You have run the 3CX "Firewall Checker" and comes up as Green, but you still have audio issues and calls
dropping on on outbound / inbound calls. Can SIP ALG be the culprit? - (answer) True
An extension will be allowed up to 25 attempts (default) for authenticating successfully, after what it will
be blacklisted for the default blacklisting interval of 1800 minutes. - (answer) False
The 3CX SIP port should be filtered by firewall ACL rules to maximize security and allow only trusted IPs
to reach it (VoIP providers or STUN extensions if any). - (answer) True
SRTP will secure calls so that a middle-man can't see the SIP traffic in plain-text. - (answer) False
, 3CX ADVANCED CERTIFICATION EXAM 2023-2024 ACTUAL EXAM 100 QUESTIONS AND CORRECT
DETAILED ANSWERS
CID and DID "Inbound Rules" can both be configured to route calls differently depending on the Office
Hours. - (answer) True
"Prepend" will add digits to the end of the dialed number before sending hte call to the destination
defined in the "Route" - (answer) False
Your Local IP Phone loses the Registration to 3CX and you want to troubleshoot the issue. You should
start a Wireshark Capture on the 3CX Server, reboot the phone, and then apply the Filter
sip.Cseq.Method==SUBSCRIBE in order to see if registrations are reaching 3CX. - (answer) False
The "Server Activity Log" will provide information for: Phone Registrations, Gateway and SIP Trunk
Interactions, All Related Calls - (answer) True
Each extension gets a default password which is always the same and should be changed for more
safety. - (answer) False
You are debugging an audio issue using wireshark by analysing the RTP streams. While using the RTP
Stream analysis tools you see that the MAX Delta of packages from the Provider to 3CX is 8-- MS while
the Max Delta for the reverse direction is 20 Ms. The issue is located at the provider end and not 3CX
end. - (answer) True
If you want to check 3CX routing of a call then only a Wireshark capture is needed, - (answer) False
Knowing only the FQDN/port of 3CX and the MAC address of a phone I could guess its provisioning URL.
- (answer) False
An outbound call is routed through the VoIP Provider. This "Route" of the "Outbound Rule" has "Strip
Digits" set as 0 and has no values in the "Prepend" field. A user dials 004433272020. 3CX will send the
call to the provider exactly as dialed - (answer) True
You can use the same VoIP Provider in all of the Outgoing Routes of a rule - (answer) True
DETAILED ANSWERS
In the criteria of the "Outbound Rules", "Calls from Extension(s)" having comma separated values will
allow multiple extension ranges to be defined - (answer) True
The Virtual Extension of the slave must match the master side virtual extension number - (answer)
True
For extensions that are registered over multiple site-to-site VPNs, by default 3CX delivers the audio
between phones if they are on different subnets. - (answer) False
On outbound calls to external numbers, 3CX will process "Outbound Rules" in a "Best Matching" way,
depending on how many of the criteria match. - (answer) False
Wireshark can - without any additional Plugins Decode all Codecs including G711A, G711U, GSM, G729,
G726 - (answer) False
STUN extensions can be configured to connect to the tunnel port of 3CX instead of the SIP port for more
security. - (answer) False
The log files of 3CX are never cleaned even when you restart the 3CX Services - (answer) False
Once Secure SIP has been configured in 3CX, Secure SIP certificates will need to be deployed manually in
phones and softphones OS so that they can communicate. - (answer) False
Remote extensions may be provisioned using the HTTP or HTTPS URLs - (answer) False
The default Voicemail PIN of an extension consist of 4 random alphanumerical characters. - (answer)
False
Your 3CX has only one SIP Trunk and receives a call from number 8135791691. If you have a "Inbound
CID Reformatting" rule on the Trunk with "Source Pattern" 813(...)(.*) and "Replace Pattern" \1\2, the
extension that receives the call will see "5791691" as the caller ID on its display. - (answer) True
,3CX ADVANCED CERTIFICATION EXAM 2023-2024 ACTUAL EXAM 100 QUESTIONS AND CORRECT
DETAILED ANSWERS
When 3CX has been installed without a FQDN from 3CX and in split DNS mode, the DNS server must not
be installed on the same machine as the phone system. - (answer) True
Your Local IP Phone loses the registration to 3CX and you want do troubleshoot the issue. You should
start a Wireshark Capture on the 3CX Server, reboot the phone, and then apply the Filter
sip.Cseq.Method==REGISTER in order to see if registrations are reaching 3CX - (answer) True
Your 3CX has only one SIP Trunk and receives a call from number 422033272020 and you want it to be
presented on the extension display as +44272020. You can do this with a "Inbound CID Reformatting"
rule on the Trunk with "Source Pattern" 44(..)(..)(.*) and "Replace Pattern" +44\3. - (answer) True
When selecting the option "I need a 3CX FQDN" an internal DNS is not mandatory - (answer) True
The order of "Inbound Rules" is not important when you have DID and CID "Inbound Rules", CIDs always
have higher priority. - (answer) False
You have a Master Bridge with 3-digit extensions 1xxx and a Slave Bridge with 4-digit extensions 2xxx. In
the "Outbound Rules" you use to rote calls across the bridge, using a prefix is mandatory. - (answer)
False
You have run the 3CX "Firewall Checker" and comes up as Green, but you still have audio issues and calls
dropping on on outbound / inbound calls. Can SIP ALG be the culprit? - (answer) True
An extension will be allowed up to 25 attempts (default) for authenticating successfully, after what it will
be blacklisted for the default blacklisting interval of 1800 minutes. - (answer) False
The 3CX SIP port should be filtered by firewall ACL rules to maximize security and allow only trusted IPs
to reach it (VoIP providers or STUN extensions if any). - (answer) True
SRTP will secure calls so that a middle-man can't see the SIP traffic in plain-text. - (answer) False
, 3CX ADVANCED CERTIFICATION EXAM 2023-2024 ACTUAL EXAM 100 QUESTIONS AND CORRECT
DETAILED ANSWERS
CID and DID "Inbound Rules" can both be configured to route calls differently depending on the Office
Hours. - (answer) True
"Prepend" will add digits to the end of the dialed number before sending hte call to the destination
defined in the "Route" - (answer) False
Your Local IP Phone loses the Registration to 3CX and you want to troubleshoot the issue. You should
start a Wireshark Capture on the 3CX Server, reboot the phone, and then apply the Filter
sip.Cseq.Method==SUBSCRIBE in order to see if registrations are reaching 3CX. - (answer) False
The "Server Activity Log" will provide information for: Phone Registrations, Gateway and SIP Trunk
Interactions, All Related Calls - (answer) True
Each extension gets a default password which is always the same and should be changed for more
safety. - (answer) False
You are debugging an audio issue using wireshark by analysing the RTP streams. While using the RTP
Stream analysis tools you see that the MAX Delta of packages from the Provider to 3CX is 8-- MS while
the Max Delta for the reverse direction is 20 Ms. The issue is located at the provider end and not 3CX
end. - (answer) True
If you want to check 3CX routing of a call then only a Wireshark capture is needed, - (answer) False
Knowing only the FQDN/port of 3CX and the MAC address of a phone I could guess its provisioning URL.
- (answer) False
An outbound call is routed through the VoIP Provider. This "Route" of the "Outbound Rule" has "Strip
Digits" set as 0 and has no values in the "Prepend" field. A user dials 004433272020. 3CX will send the
call to the provider exactly as dialed - (answer) True
You can use the same VoIP Provider in all of the Outgoing Routes of a rule - (answer) True
