SIP Trunking

Take advantage of our low cost SIP Trunk line rental and call charges which are compatible with all types of telephone system that can use SIP Trunks.  Whether you need a VoIP telephony service for your Asterisk or VoIP Gateways connected to your Legacy (Analog) PBX, or need to utilise the VoIP capabilities of your Panasonic, Siemens, Avaya, Samsung, LG, Toshiba or other brand of phone system then our business quality SIP trunking services are for you.


Even if you don’t have a VoIP compatible phone system you can still take advantage of our low rates and line rental by installing a VoIP gateway which will allow you to route calls from your phone system across the internet to our SIP Trunk service.  For small business users with Analogue or ISDN BRI telephone lines you can connect any popular VoIP gateway which offers VoIP G729 connectivity for SIP Trunks as well as branch office connectivity for free calls between offices.


Line Rental Costs

Our SIP Trunks are charged at just R25 per channel per month (one channel equals 1 concurrent call), with DiD numbers charged at R20 per month each.

The cost of a SIP trunk with Telephone number to enable inbound calls is R100 for a minimum 5 channels per month compared to R875 per month for analog lines from Telkom, a HUGE saving.
These prices are based upon using your existing broadband connection to connect to our service.


Free Calls

Provided another branch is using an O-Tel SIP service, the call will be free of charge.


Call Costs

As the internet is world wide, we deliver the call as far as possible over the internet. Calling Local Landline costs R0.35c and cell phones R0.99c per minute.
In general, all SIP trunk call charges will be more cost-effective than with your present supplier.


Porting Numbers

Using SIP trunking, if you decide to move offices, you can take your Telkom telephone number with you. This is major benefit of the service. For example, if you are located in Durban with a 031 number, and move to Cape Town, you can keep your current telephone number by Porting it to our VoIP network and using SIP Trunks.


Number Provisioning

A major benefit of using SIP Trunks is the ability to use geographic phone numbers for most South African exchanges, either from your present location or numbers from exchanges around the country.

For example, you are based in Bloemfontein and require a local presence in Johannesburg, Pretoria and Cape Town. You will be provided with 051, 010, 012, and 021 numbers. The calls from these destinations will be routed to you via your broadband connection. The good news for you is you will not require 0860 or 0861 numbers, and your customers will not have to pay the inflated rates for dialling 0861, and 0860 numbers.


Why SIP Trunking ?

SIP Trunking provides the ability to make and receive telephone calls over the internet. Within the next 10 years, 90% of telephone calls world wide will be made over the internet.

SIP is a world wide internet protocol for establishing and maintaining multi-party, mixed media sessions over converged networks. SIP enables the creation and deployment of feature rich services that go far beyond simple VoIP calls. SIP provides an open programming protocol for voice, text and video applications.

SIP is the signalling protocol which allows mixed-media sessions of text, voice and video applications using existing devices, including PC/laptops, PDA’s and future smart phone technology.


At the residential end of the market, companies such as Skype have had 100 million downloads of their software; millions of people are making free calls between friends and family over the internet across the world.


As the commercial version of the residential product, SIP trunking is more resilient and will interconnect with the present voice networks worldwide.


SIP trunking has the full backing of Ofcom (the telecommunications governing body) which has allowed more flexibility compared to the present voice network.

SIP Trunks and VoIP Calls - FAQ

Can I use my present broadband connection?

This depends on the size of your broadband and how many simultaneous calls you want to make over the connection.  The size of a SIP voice call is 20Kbitps, so if you have an upload of 256Kbitsps, you could have 12 calls (without any additional data) over one dedicated connection.

Can I discontinue my present lines?

We would always recommend you keep a percentage of your analogue or ISDN telephone lines as back up.  In the event of your broadband connection going down, we will route calls to an alternative telephone number/s.  Most VoIP Phone systems are configured to use existing Analogue and ISDN Telephone Lines as well as SIP Trunks.


Do I need to change my telephone System ?

Many new telephone systems will support SIP trunks; we have tested, and are approved by most manufactures.  We can provide conversion units (VoIP Gateways) which connect to your existing telephone system to convert analogue / ISDN trunks to SIP Trunks.  This will allow you to take advantage of SIP Trunks and VoIP Calls without upgrading your current telephone system.

Are there any setup charges?

Some services have FREE set up and other SIP trunk services have a small set up charge.  To get details of the services we provide and their set up and rental charges, it will be listed on each services SignUp page.


How do I port my numbers?

There is a simple form to be completed which we then send to Telkom, the process takes 14 working days.

How Resilient is the VoIP network?

The major benefit of the internet is there is no single point of failure. As a company, we have equipment based in separate locations, should one connection fail the call will be automatically routed to an alternative location.