Specifications

AddingaVoIPProvider/SIPTrunk
Introduction
VoIPproviders“host”phonelinesandarereplacingthetraditionaltelcolines.VoIP providers can
assignlocalnumbersinoneor morecitiesorcountriesandroutethese toyourphonesystem.In
mostcasestheyalsosupportnumberporting.
VoIP providers are often able to offer better call rates because they may have an international
network or have negotiated better rates. Therefore, using VoIP providers can reduce call costs.
However, be aware that each VoIP call requires bandwidth. VoIP is real time, so it does place a
demandonyourInternetconnection.Asaruleofthumb,eachcallwillconsumeapproximately30
120kbpersecond,dependingonwhichcodecyouuse.Thedocument,BandwidthOverheadover
DSLconnections,includesdetailedinformationaboutbandwidthconsumption,includingparticular
codecsbandwidthusage.
3CXrecommendsusingsupportedVoIPproviders.AllsupportedVoIPprovidershavebeentested
for interoperability with 3CX Phone System, and are retested with each new build. Their
configurationtemplatesarealsoincludedwith3CXPhoneSystemtoallowyoutoquicklyandeasily
addthem.Seethelistof3CXSupportedSIPTrunkProviders
3CXPhoneSystemsupportstwotypesofVoIPProviders:
● RegistrationBased – TheseVoIP providers require thePBX to register withthe provider
using an authentication ID and password. Most of the VoIP providers predefined in 3CX
PhoneSystemareregistrationbased.
● IP Based / SIP Trunk – IP Based VoIP Providers (also known as SIP Trunks) do not
generallyrequirethePBXtoregisterwiththeprovider.TheIPaddressofthePBXneedsto
be configured with the provider, so that it knows where calls to your number should be
routed.
RequirementsforusingaVoIPProvider/SIPTrunk
If you plan to use a VoIP provider, you need to have a firewall/router/NAT device that supports
STATIC PORT MAPPINGS. Often routers will perform port address translation, which will cause
problemssuchasonewayaudio,failinginboundcallsandsoon.Itisalsohighlyrecommendedthat
you have an External FQDN that resolves to a static external IP. If your external IP changes
intermittently, inbound calls will fail. See the Firewall & Router Configuration for details need to
configureyourfirewall/router/NATdevice.
ConfiguringaVoIPProvider/SIPTrunk
Step1:CreateanAccountwithaVoIPProvider
Firstoff,youneedtohaveanaccountwithaVoIPserviceprovider.3CXPhoneSystemsupports
mostpopularSIPbasedVoIPserviceprovidersandwerecommendusingonethathasbeentested
by3CX. As 3CX includespreconfigured templates for theseVoIP providers. Simply select“VoIP
Providers”>“AddVoIPProvider”buttontoseealistofsupportedproviders.
IfthereisnoVoIPproviderinyourcountryyoucanuseSkypeforSIPwhichhasaglobalpresence.
Step2:AddtheVoIPProviderAccountin3CXPhoneSystem
After you have createdthe VoIP provideraccount, you willneed to configurethe account in3CX
PhoneSystem.Todothis:
1. In the 3CX Phone Management console menu, select “VoIP Providers” > “Add VoIP