How to protect your VoIP phone system

With many benefits that come from using a VoIP (Voice Over IP) Phone System, such as their low price and technological advances unbeknown to landlines, come cybersecurity risks that are common for everything that is based on the internet. Any system that uses port and internet connection can be accessed by third parties, costing you time, money, and human resources to mend the damages they’ve done. Instead of going into battle against the hackers’ attacks, it makes much more sense to prevent them by following the recommended tips for protecting the VoIP phone system.

Here is a list of things to consider to ensure the security of your VoIP system.


A secure firewall for a VoIP system is an absolute necessity. Whenever you make a phone call, Session Initiation Protocol (SIP) contacts and establishes the connection with the receiving phone. Other protocols take over carrying the call, but in the end, it’s SIP again that terminates the call when you hang up. Although there are vulnerabilities to it, SIP is an irreplaceable protocol for your VoIP system security, as well as regularly updated OS on every device that uses the phone system.

Strong and often-updated passwords

Just as the rest of your data, your VoIP phone system requires careful handling of the passwords. Create passwords that contain a minimum of 12 characters, including numbers, letters (lower and upper case), and special characters. The best passwords are random series of characters. Alternatively, the NCSC advises using hard-to-guess passwords by “combining three random but memorable words” in individual devices. Remember to set a password immediately after setting up the VoIP system, or else you won’t remember to do that later, or it even may be too late. VoIP phones often come with factory-set passwords that can be available publicly on the web. Passwords should be regularly changed – every two to three months!

Network monitoring

Network monitoring is the crucial element of your VoIP security. Designed primarily to assure the quality of service (if you’re a call centre or customer support, you’ll want to analyse and improve the quality of calls), network monitoring shows you data about traffic, including the anomalies. Hackers’ attacks are especially prone to their devious activity when you’re not expecting them – during night hours and weekends. Because they assume you do not monitor your network at those times, they’ll try to use your system for making expensive international calls, creating substantial financial losses for your company. To prevent this from happening, you can either assign a person to be a “night guard” and monitor the activities or more pragmatically and less costly, fire up an automated alert system. The business phone provider of your choice needs to provide the necessary technology and logistic support. According to this RingCentral alternatives review, you can choose from different providers that ensure good quality of VoIP service, while offering support in your cybersecurity management.

Use Virtual Private Networks (VPNs)

If your employees use the VoIP phones remotely, VPNs will protect you from establishing corrupted connections. Their role is to create virtual tunnels for sending and receiving data, securing access to the onsite networks. The data stays encrypted, whether you are placing, or receiving a call. Make sure that your VPN provider gives you sufficient bandwidth in the tunnel, or else the quality of calls may suffer.

Use data encryption

Speaking of encryption, VPNs are not the only element of encryption. Basically, there are three “doors” that can let in intruders. The first one belongs to the initiator of a call and their device. The other end is the one that belongs to the receiver of the call. In the middle, there is the data within the phone call (the conversation that we hear). VPNs make sure that these ports are secure, but you’ll need other protocols and layers to encrypt the actual data – voice conversations. As a result, encrypted data can’t be used by hackers, even if they manage to intercept the calls.

Disable web interface use

If possible, don’t use a web interface for your VoIP phone system. When you use phones on your desktop computers, you’re opening a whole new area of weakness to hackers. If anyone of your phone users falls prey and exposes the system to an external party, your entire VoIP data can be stolen as a plain text. If you must use the web interface, make sure to handle the security very strictly.

Train your employees

Just as mentioned earlier, a lot of weakness of VoIP security comes from irresponsible users’ behaviour. All the users need to know how to handle passwords, how to spot unusual network activity, and which security protocols to follow – to ensure safety. Besides the onboarding training in cybersecurity, organise training periodically to keep the system tight and safe!

Avoid international phone calls

Does your business need to make international VoIP calls? If you’re a locally-based business with local customers, it’s best to disable the international calls option. The reason is that one of the most common motives for hackers to take an interest in your VoIP phone system is to take advantage of your weak security and make tons of expensive international calls. If you do need to make and receive international phone calls, make sure to closely monitor your network for suspicious activity – as you’ll read in the next tip.

Once you dive into VoIP system security, you’ll discover there is more to it than meets the eye. If you’re a business owner that wants to handle business responsibly, you’ll see to it that your VoIP is fully protected.

Milica Kostic is a Content Development Specialist at Fortunly and a Blogger at SmallBizGenius, Techjury and Hosting Tribunal. With a degree in Sociology, she is very passionate about writing, focusing on many of the social phenomena affecting our society today. Besides finance, she is also interested in cybersecurity, marketing, technology, the environment, customer and employee experience.

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