What is SIP Trunking?

When you order at a restaurant, you might ask the server how your steak is cooked, but you’re probably not going to go into the kitchen and have the line cooks explain each step that your meal goes through before it comes to your table. As long as what you order looks and tastes good, you’ll be satisfied.

A lot of people look at their business communications technology the same way. As long as your phone calls go through and you know how to dial out, who cares what goes on in the space between your phone and your customers?

But when your system stops working, you’re probably going to have a few more questions.

That’s why it’s a good idea to get a solid understanding of what’s going on with your phone system, especially when it comes time to buy a new one.

When you’re looking into VoIP calling, you’ll hear a lot about SIP trunking. Keep reading to learn what SIP trunking is and how to determine if it’s the right option for your business.

How VoIP Works (Briefly)

Voice over Internet Protocol (VoIP), as you may know, is the process by which voice data is transferred over Internet lines for the purpose of making phone calls. VoIP stands in contrast to standard analog phone systems, which typically use the Public Switched Telephone Network (PSTN).

There are a few different ways that companies can implement a VoIP system, but the majority of them utilize SIP trunking.

What is SIP Trunking?

The SIP in SIP trunking stands for Session Initiation Protocol, and it’s one of the most popular ways to implement a VoIP system.

How it Works

To make VoIP calls, a connection must occur between your private business network and the public network, usually the PSTN. The SIP trunk facilitates this connection and allows calls to flow freely and be prioritized correctly over your internet connection.

Unlike other options, SIP trunking allows multiple calls at the same time to be transferred through a network and delivered to your phones without having to purchase more hardware. Other trunking solutions can only accommodate so many calls at once before you are forced to upgrade your hardware, which can end up being a major expense in a scenario like a call center.


It is possible to run an SIP trunk directly over the internet connection in your home or office. However, best performance occurs when a dedicated data line is used. Your VoIP provider can help you to understand what needs to be installed to maximize the effectiveness of your SIP trunking setup.


As long as your company has the bandwidth to support the calls you want to make, the capacity will not be limited by your SIP trunk. Rather, because of the virtual connection, the bandwidth of your data line between you and your VoIP provider will be the only thing that limits VoIP calling capacity.

Further, SIP trunking is useful beyond voice calls. Specifically, implementing SIP trunking is extremely effective when it comes to implementing unified communications.

Do You Need SIP Trunking?

In most cases, SIP trunking is the most cost-effective way to implement a VoIP system. While the same solution may not be ideal for every business, it is certainly worth considering if you are looking to upgrade your communications system and maximize productivity for your employees.

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