3CX Academy, Advanced Certification
COMPREHENSIVE TEST BANK MIDTERM EXAM 2026-
2027 NEWEST EXAM WITH COMPLETE QUESTIONS
AND CORRECT DETAILED ANSWERS\VERIFIED 100%
ALREADY GRADED A+ \LATEST UPDATE BEST FOR
EXAM PREPARATION
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?
ANSWERS: 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.
ANSWERS: 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).
ANSWERS: True
SRTP will secure calls so that a middle-man can't see the SIP
traffic in plain-text.
ANSWERS: False
CID and DID "Inbound Rules" can both be configured to route
calls differently depending on the Office Hours.
ANSWERS: True
"Prepend" will add digits to the end of the dialed number
before sending hte call to the destination defined in the
"Route"
ANSWERS: 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.
ANSWERS: False
The "Server Activity Log" will provide information for: Phone
Registrations, Gateway and SIP Trunk Interactions, All Related
Calls
ANSWERS: True
Each extension gets a default password which is always the same
and should be changed for more safety.
ANSWERS: 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.
ANSWERS: True
If you want to check 3CX routing of a call then only a Wireshark
capture is needed,
ANSWERS: False
Knowing only the FQDN/port of 3CX and the MAC address of a
phone I could guess its provisioning URL.
ANSWERS: 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
ANSWERS: True
COMPREHENSIVE TEST BANK MIDTERM EXAM 2026-
2027 NEWEST EXAM WITH COMPLETE QUESTIONS
AND CORRECT DETAILED ANSWERS\VERIFIED 100%
ALREADY GRADED A+ \LATEST UPDATE BEST FOR
EXAM PREPARATION
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?
ANSWERS: 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.
ANSWERS: 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).
ANSWERS: True
SRTP will secure calls so that a middle-man can't see the SIP
traffic in plain-text.
ANSWERS: False
CID and DID "Inbound Rules" can both be configured to route
calls differently depending on the Office Hours.
ANSWERS: True
"Prepend" will add digits to the end of the dialed number
before sending hte call to the destination defined in the
"Route"
ANSWERS: 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.
ANSWERS: False
The "Server Activity Log" will provide information for: Phone
Registrations, Gateway and SIP Trunk Interactions, All Related
Calls
ANSWERS: True
Each extension gets a default password which is always the same
and should be changed for more safety.
ANSWERS: 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.
ANSWERS: True
If you want to check 3CX routing of a call then only a Wireshark
capture is needed,
ANSWERS: False
Knowing only the FQDN/port of 3CX and the MAC address of a
phone I could guess its provisioning URL.
ANSWERS: 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
ANSWERS: True
