9.19.2022 Blog

What is an SBC and what are its functions?

Nobody wants to be a victim of a cyber-attack. Toll fraud in particular is often overlooked as a cyber-attack and can cause lots of money and damage to your network.

Cyber-attacks can ruin your network and cost your business valuable time and money as a result. Additionally, dropped calls or bad call connections can lead to frustrations and potentially lost customers with whom you may have been on the phone.

Cyber-attacks can cost your business hundreds of thousands of dollars to repair. However, cyber-attacks do not always mean attacks on your computer or software; they could also mean attacks over calling.

The number of network security options that are available on the market can be a little overwhelming. While there are tons of security options to protect your network there are not nearly as many call security options.

Coeo has sold hundreds of thousands of SBCs and has helped secure the networks and call paths of all kinds of customers. Additionally, we are currently offering a promotion to customers purchasing SIP Trunking and SBCs from Coeo.

We know how frustrating it can be to be a victim of a cyber-attack and lose connection on a call which is why we want to educate you on SBCs as a potential to help your organization.

By the end of this article, you will know what SBCs are and their functions. This will help you make a better buying decision on SBCs and help you determine if they are a good fit for your network.

What is an SBC?

A Session Border Controller (SBC) is a dedicated software or hardware device that controls how phone calls are initiated, conducted, and terminated on a voice-over-Internet Protocol (VoIP) network.

SBCs act as a router between a network and a carrier service ensuring that all calls are secure and have the highest quality of service possible. An SBC can also serve as a purpose-built firewall specifically for voice that can identify incoming threats.

SBCs often provide access control and data conversion for calls. This goes for both voice and video calling as SBCs help with both.

SBCs are typically deployed at the edge of the network as well as the demarcation points between users and other service providers. SBCs in today’s technology is usually focused to support and secure SIP infrastructures.

SBCs secure a core SIP Trunking network and provides client and server connection. While SIP has been evolving and gaining traction over the last two years, SBCs are valuable in providing connection between disparate protocol versions and optional headers.

With modern SBCs the signaling and media components operate as individual elements integrated into the network. This allows each function to be located in its ideal physical and logical layer.

SBC Functions

There are many functions that SBCs have that an organization can benefit from. The general functions of SBCs include:


Having connectivity with other networks always comes with added risks and the need for security. Cyber-attacks are always a pain to look out for when talking about network security.

Additionally, toll fraud is another attack you have to watch out for that often gets overlooked. Toll fraud is when a cybercriminal gains access to your phone system to make artificially generated calls.

These calls are then purposely made to expensive rate numbers and a part of the revenue is given to the cybercriminal. Organizations spent over $9 billion in 2021 due to toll fraud losses.

An SBC serves as a purpose-built firewall specifically for voice, protecting your network from cyber-attacks. SBCs can also secure your calling paths which will protect you from voice-specific attacks such as toll fraud.

SBCs can also use something called pattern recognition as a means of flagging any unusual activity. Pattern recognition is the method used to recognize patterns and regularities in data to detect possible uncovered attacks.

Interworking Protocols

Having an SBC can allow you to connect different protocols and will enable them to be translated between each other.

Since there are multiple different versions of SIP like SIP H.323 and SIP-I, SBCs allow for these different versions and protocols to translate between each other.

With an SBC, multiple protocols can communicate with each other making connectivity more stable. Organizations can route phone traffic through internal IP networks which allows for calls to be routed much faster and saves you money as well.


An SBC acts as a demarcation point between your network and your service provider.

Connecting all of your different devices such as printers and phones to your network can be hard to manage. With an SBC, they can all connect together and to your service provider without much hassle.

When different devices are connected to your network such as phones and printers, as well as different service provider communications it can be hard to manage. The SBC can help manage these connections and make it less of a hassle.

Next steps to securing your network

Now you know what an SBC is and its functions and you will have a better idea of if an SBC is the right fit for your network. There are many network security options on the market and it can be hard to figure out which service(s) is right for you.

Nobody wants to be a victim of a cyber-attack and while there are plenty of solutions to protect your network, there are not very many solutions to protect your voice. With an SBC, you can use it as a purpose-built firewall that protects your voice and calling.

Coeo has helped thousands of customers secure their network. We know just how frustrating it can be to be a victim of a cyber-attack and hope that learning about SBCs can help you make an educated decision on security.

Some relevant next steps you can take would be to learn about SIP Trunking by reading this article:

Additionally, if you would like to learn more about network security, you can read these articles:

After reading these articles and continuing to educate yourself on network security, you can talk to our sales team. If you have any questions or want to make a sales appointment, you can schedule an appointment to talk with our team.

Get in touch at 844.300.2636(COEO)

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