SIP Trunking Providers – What’s the Difference Between Them?

All SIP Trunking Providers are not Created Equally

With the growing popularity of SIP trunking and cloud-based communications, it’s not surprising that there are a lot of vendors who offer SIP services.  In fact, many SIP trunking providers can lower your phone bill, but that does not mean they are all the same.  It is important to understand what each SIP provider can deliver and what sets one apart from another.  Here are a few areas to explore as you evaluate SIP trunking providers.


You don’t need to become a SIP expert or understand the minute details of how it works, but it is important to choose a provider with an infrastructure that can meet your needs and protect you from service interruptions.  The best practice is to utilize a Tier 1 network with gateways in several disparate locations.  Ensuring your SIP vendor meets these requirements will minimize your risk that a single data center failure will impact your ability to make and receive calls. All SIP trunking providers should meet this standard, but not all do, so it’s important to ask.


Another big difference in SIP providers relates to connectivity.  Some SIP trunking vendors require that you purchase Internet connectivity from them.  This is a profitable line of business for these companies, but it limits the buyer’s ability to shop for the best price and the best service for their particular needs and location.  Choosing a vendor that gives you the choice of high-speed Internet connectivity puts you in the best position to maximize savings and performance.


One of the main reasons for choosing the SIP approach over traditional telephone lines is the flexibility it offers. Business can be difficult to predict, so you want to be able to add or cancel channels as needed.  This means you need a SIP trunking provider that not only allows you to add or remove lines without any long term contract or obligation but also one that offers simple self-service tools that make it easy for you to make changes on the fly as the needs of your business evolve.


You are likely considering SIP trunking as a way to reduce telecommunications costs.  This can make it tempting to choose the SIP vendor with the lowest per-channel price.  But, it is important to understand both the per-channel cost and the other possible fees including; setup, toll-free service fees, extra charges for direct inward dialing (DID), and porting costs.  International calling is another area to consider if it is a requirement for your business. It’s best to do business with a SIP vendor that is upfront about all fees, contract obligations and support offered. Two vendors with the same per trunk cost may turn out to have very different bottom-line costs, so look carefully.

PBX Compatibility

Just as there are a wide range of SIP trunking providers in the market, there is also a wide range of IP-PBX options.  You’ll need to select a SIP solution that is compatible with the PBX of your choice. Two of the most popular open-source PBX solutions are Asterisk and FreeSwitch.  Unfortunately, many SIP trunking providers can not support these solutions, so it is an important area to consider during your vendor search.


You don’t likely implement SIP trunking services every day, but some vendors assume that you know the ins and outs of implementation and can do it alone.  This may be a common attitude, but it isn’t universal.  Look for a SIP solutions provider that will assist with set up and be there for ongoing support as needed.

All SIP trunking providers are not created equally.  Voice communications are important to your business, so it is wise to take the time to understand what each vendor has to offer and make the selection that makes the most sense for your business.