3CX Academy, Advanced Certification questions and answers well illustrated.

3CX Academy, Advanced Certification questions and answers well illustrated. In the criteria of the "Outbound Rules", "Calls from Extension(s)" having comma separated values will allow multiple extension ranges to be defined - correct answers.True The Virtual Extension of the slave must match the master side virtual extension number - correct answers.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. - correct answers.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. - correct answers.False Wireshark can - without any additional Plugins Decode all Codecs including G711A, G711U, GSM, G729, G726 - correct answers.False STUN extensions can be configured to connect to the tunnel port of 3CX instead of the SIP port for more security. - correct answers.False The log files of 3CX are never cleaned even when you restart the 3CX Services - correct answers.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. - correct answers.False Remote extensions may be provisioned using the HTTP or HTTPS URLs - correct answers.False The default Voicemail PIN of an extension consist of 4 random alphanumerical characters. - correct answers.False Your 3CX has only one SIP Trunk and receives a call from number 1. If you have a "Inbound CID Reformatting" rule on the Trunk with "Source Pattern" 813(...)(.*) and "Replace Pattern" 12, the extension that receives the call will see "" as the caller ID on its display. - correct answers.True 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. - correct answers.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 - correct answers.True Your 3CX has only one SIP Trunk and receives a call from number 020 and you want it to be presented on the extension display as +. You can do this with a "Inbound CID Reformatting" rule on the Trunk with "Source Pattern" 44(..)(..)(.*) and "Replace Pattern" +443. - correct answers.True When selecting the option "I need a 3CX FQDN" an internal DNS is not mandatory - correct answers.True The order of "Inbound Rules" is not important when you have DID and CID "Inbound Rules", CIDs always have higher priority. - correct answers.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. - correct answers.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? - correct 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. - correct 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). - correct answers.True SRTP will secure calls so that a middle-man can't see the SIP traffic in plain-text. - correct answers.False CID and DID "Inbound Rules" can both be configured to route calls differently depending on the Office Hours. - correct answers.True "Prepend" will add digits to the end of the dialed number before sending hte call to the destination defined in the "Route" - correct 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. - correct answers.False The "Server Activity Log" will provide information for: Phone Registrations, Gateway and SIP Trunk Interactions, All Related Calls - correct answers.True Each extension gets a default password which is always the same and should be changed for more safety. - correct 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. - correct answers.True If you want to check 3CX routing of a call then only a Wireshark capture is needed, - correct answers.False Knowing only the FQDN/port of 3CX and the MAC address of a phone I could guess its provisioning URL. - correct 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 020. 3CX will send the call to the provider exactly as dialed - correct answers.True You can use the same VoIP Provider in all of the Outgoing Routes of a rule - correct answers.True If you want to decode audio in wireshark without any plugins, your calls will need to be using either G711A or G711U - correct answers.True If you want to check the internal PBX routing of a call, the most reliable way is through the use of the Binary Log Viewer, or which you must know some information about the call you are investigating, like the Caller ID, the time of the call, etc. - correct answers.True Assume the following scenario: 3CX is connected via a site-to-site VPN with two different buildings where remote phones have been provisioned. 3CX is on network , Phones on location A are on network , Phones on location B are on network . When a call is established, between an extension on