Kiwilink SIP Trunks

A SIP Trunk allow you to route concurrent calls over the Internet to an IP capable PBX system. Kiwilink uses the SIP protocol to deliver calls to your PBX platform. If you do not have a PBX or VoIP Gateway - or your existing PBX/gateway is not SIP capable then the Kiwilink SIP trunking service is not for you and you should never enable this feature on your account.

SIP trunking can be seen as a low cost replacement for traditional PRI or analog circuits - using the Internet to make/receive calls instead. This means cost savings since you do not need to order expensive circuits from a legacy telecommunications provider and can use your existing broadband connection to terminate/place calls.

We have 2 SIP Trunk plan options below or see our bundled plans for competitive plans

Plans SIP Trunk SIP Trunk 2000 local mins
Monthly Charge $11.50 $20
Phone line NZ local DDI NZ local DDI
Calls to other Kiwilink customers Free Free
NZ Local 3c a minute 2000 free mins then 3c a minute
NZ National 5c a minute 5c a minute
Mobile 22c a minute 22c a minute
UK, USA, China, Australia 8c a minute 8c a minute
Other International All calls at standard VoIP call rates All calls at standard VoIP call rates
No of SIP Channels 5 shared channels (ie 5 concurrent calls). An extra 5 channels is available at $10 per month 5 shared channels (ie 5 concurrent calls). An extra 5 channels is available at $10 per month
Additional DDIs with no call features $2.50 per month each or 
block of 10 naked DDI for $25
$2.50 per month each or 
block of 10 naked DDI for $25

All prices are exclusive of GST

SIP trunking is primarily used by businesses. To setup SIP trunking you will need the following:

  • A static Internet (IP) Address. Dynamic DNS hostnames are not allowed. You must specify an IP address in Kiwilink Live to act as your endpoint for inbound calls.
  • No firewall rules or NAT blocking traffic between Kiwilink’s servers and your IP-PBX. You may setup firewall rules to limit traffic to Kiwilink’s servers or setup port forwarding if required for security reasons. See below for more details.
  • You need a SIP (v2) compatible PBX platform or gateway. Kiwilink does not support H.323 or other VoIP protocols. A popular example of an IP-PBX platform is Asterisk/Trixbox, although there are a multitude of other hardware versions such as the Epygi gateways for example.

If you are unsure whether your IP-PBX is compatible with Kiwilink then contact for more information.

You do not always need to have SIP trunks with an IP-PBX. Many IP-PBX platforms can register (login) with Kiwilink as a normal phone would. In fact this is what many Asterisk users do using the ‘register’ directive in their SIP configuration. If you do not have a static IP address or your IP-PBX is behind NAT then you cannot use SIP Trunking and you will need to register your devices with Kiwilink and use the ‘Inbound trunking’ feature on each line instead to achieve a similar goal.

Many IP-PBX’s cannot be configured to register/login to Kiwilink as a client, so for these types of devices SIP trunking is the only way you can interconnect with Kiwilink. SIP trunking has many other benefits over a dynamic registration including:

  • Your device does not need to be logged in or registered, so calls will always be routed to your IP-PBX. This means that if your internet connection was reset or went down temporarily you would start receiving calls immediately once your internet connection comes back up (instead of having to wait for a re-registration or login)
  • You can route all your numbers easily to your IP-PBX with no further configuration required. If you add more numbers to your account then they will automatically be routed down your trunk.
  • SIP trunks have the concept of a ‘pilot’ number. You can present any caller ID number down your trunk and if it is not recognised as being on your account then the caller ID will be set to the trunk number. This makes configuration simpler and avoids outbound calls ever being rejected.
  • You save bandwidth since there is no need for SIP registrations or ‘polling’ traffic usually sent to devices that are behind NAT.

Can I login to Kiwilink with a phone while I have SIP trunking enabled?

No, you cannot have SIP trunking enabled on the account at the same time as logging in/registering from another phone/device. When you enable SIP trunking on your account you instruct Kiwilink to always send calls to your IP-PBX system and nowhere else. If you try to login/register to Kiwilink on one of your numbers while SIP trunking is enabled then you login/registration will fail. If you want to use SIP trunking and a standard VoIP phone with Kiwilink then you will need to setup 2 separate accounts to do this.

Asterisk Security?

Asterisk is often hacked if you don't know what you are doing (for example 'guest mode' is enabled in older versions of Asterisk by default which means that anybody can make calls through the PBX without any authentication). If you have setup port 5060 for forwarding to a PBX with no firewall rules to restrict IP addresses allowed to connect and either has guest mode enabled or a very week password scheme then you run at a high risk of having your Asterisk sever being hacked.

Best practices are to either:

a) Have your PBX/Device behind a firewall or router doing NAT and do not 'port forward' ports to the PBX or place the IP PBX in a DMZ so it is exposed to the Internet and open to being hacked.  The vast majority of customers will be okay as they place their devices usually behind a router and rely on NAT to get packets in/out of their network, but a few people out there still insist on putting their PBX in a DMZ or set up port forwarding rules
b) If a customer does 'SIP peering' (so they are not behind NAT) - then it is best to setup a firewall rule so that *only* Kiwilink's IP address ( can talk to the customer device, so the rest of the Internet cannot connect to SIP port 5060 for example and start a hacking attempt.
c) Obviously all passwords should be *strong* (8 characters, letters and numbers etc. and hard to guess)

How do I configure my IP-PBX to connect to Kiwilink?

This of course depends on what type of IP-PBX you are using. The main setting you need to configure is the ‘host’ or ‘proxy’ address of your outbound trunk. You should set this to:

NOTE: This is different to the default host name you use to connect to Kiwilink (which is The rest of your settings will likely be specific to your PBX platform. If you must enter an IP address as your host then perform a lookup of the above host name to find out it’s IP address (In windows you can open a command windows (Star -> Run -> ‘cmd’) and type ‘nslookup’. The IP address may differ depending on your geographical location etc.

One of the most common IP-PBX platforms in use today is Asterisk (or one of it’s variants such as TrixBox). Below is an example ‘SIP peer’ definition for Asterisk allowing you to route calls to Kiwilink via your SIP trunk:


This is only an example. You will need to decide which codecs and context you wish to use in your own setup. You may then route calls out through your Kiwilink trunk by adding a directive such as the one below into your extensions configuration:

exten => _X.,1,Dial(SIP/Kiwilink/${EXTEN},,T)