đź“ž +1 (858) 379-6653

Network Security in VoIP – 8 Ways You Can Strengthen It

8 Ways to Strengthen Network Security for VoIP

Voice over IP (VoIP) has evolved a lot from where it started. It doesn’t have the same availability and performance issues it used to have in the beginning. VoIP providers have integrated quality-of-service (QoS) technology and built high-speed networks to mitigate those performance issues. Yet, concerns over VoIP security remain the same as they were before.

Security risks over the internet have increased over the years. Since 2014 cyber threats have increased by 67%, which makes VoIP conversations unsafe as they run on IP networks. While you can secure your IP network, ensuring security in Internet telephony is not easy. Understandably, businesses are wary of deploying VoIP because of security issues.

In theory, voice over an IP infrastructure isn’t more or less secure than any other software running on data packets. This is why to ensure VoIP security, we must examine VoIP security as an extension of IP data and traditional telephone and consider all security threats that both these domains face.

In this article, we will list down 8 ways to ensure network security for VoIP and make communication safe.

Tunneling Protocols

A tunneling protocol is a communication protocol used in VoIP and other computer networks. The protocol facilitates the transmission of data from one network to another. Tunneling protocols use encapsulation to transmit private network data across public networks such as the Internet.

In the context of VoIP communications, tunneling protocols enable service providers to encrypted VoIP calls that can connect to any VoIP service. We embed encryption in these connections to ensure the privacy of users and guarantee that third parties (or governments) cannot block VoIP traffic.

VoIP tunneling protocols can bypass firewalls configured with VoIP blockages. These tunneling protocols encode and decode data packages sent and received from the tunnel. It utilizes a portion of the data packages to transmit the packets that provide the VoIP service.

Tunneling uses a layered protocol model similar to the TCP/IP or OSI protocol suite. However, these protocols violate layering models while using payloads to carry a service that the network doesn’t normally provide. In most cases, the delivery protocol will function at a higher or an equal level in the layered model compared to the payload protocol.

Why Are Tunneling Protocols Necessary for VoIP-Enabled Protocols?

In most cases, VoIP blockages occur due to the monopoly of major telecom companies in a particular region. Blocking VoIP forces businesses and consumers to use the local phone system instead of cost-efficient VoIP services. In countries like UAE block VoIP services because VoIP can kill a major source of their revenue generated from government-owned telecoms.

On the other hand, some governments implement VoIP blockages because it is hard for them to track encrypted VoIP connections. As a result, they block all VoIP, irrespective of the nature of the VoIP connection. Countries like China block all VoIP services unless government-backed companies such as China Telecom and China Unicom offer them.

Besides that, many organizations implement VoIP blockages due to their internal policies. Here one of the most common ways to block VoIP connections is to block the ports a system uses. For instance, some hotels block all VoIP ports so guests only use their chargeable telephone service.

Regardless of where these VoIP blockages may happen, using a tunneling protocol alongside a VoIP connection can help businesses access these locations despite blockages.

End-to-End Encryption

VoIP happens through internet networks, so they can become victims of snooping by hackers, similar to any other IP network. However, by encrypting the information you send over the network, you make it difficult for cybercriminals to decrypt the data even if they record it. End-to-end encryption is a necessity of VoIP networks.

Wi-Fi Encryption

To ensure security on different layers of the network, businesses must add more than one security layer to their VoIP network. Calls transferred over an unencrypted Wi-Fi makes your data susceptible to snooping. Being complicit over security in internal networks can your entire VoIP infrastructure vulnerable.

Most employees readily connect their mobile phones to unsecured Wi-Fi networks. When your VoIP phones are connected to the same Wi-Fi network as other phones, it can expose all VoIP data along to cybercriminals.

Robust Password Management

For people using hosted VoIP through mobile apps, VoIP data is as secure as their device password. Therefore, setting up weak passwords on VoIP networks and phones can leak sensitive VoIP data in a password leak.

Remote Device Management

Many businesses use remote devices to enable VoIP communication for their employees. However, this can easily become a security risk and endanger data saved on those remote devices. This is why these companies must create a mechanism for wiping devices remotely.

Firmware on VoIP Phones

Although people use mobile handsets across VoIP networks, many companies still use traditional phone-like handset inside their organizations. These VoIP handsets are similar to normal phones in some ways but have sophisticated software other phones usually do not have.

The software on these phones makes them more secure than other phones. Still, businesses need to update firmware on these devices from time to time as new security threats emerge. Likewise, if you have VoIP infrastructure hardware on-premise, it becomes extremely important to patch VoIP servers regularly.

Call and Access Logs

Cyber attacks massively damage your company’s reputation. Therefore, if you don’t look for these intrusions judiciously, security on VoIP networks will always be insufficient. One way of keeping an eye on unusual activities is to analyze VoIP call logs of the company.

With the help of logs, you can easily identify the source of VoIP cyber attacks, making it easier to prevent unauthorized calls. At the same time, monitoring call logs is a brilliant way to detect brute-force password attacks and identify failed connection attempts. You can resolve these issues through a detection mechanism that alerts you when people make calls over a certain threshold.

VoIP Security Protocols

Session Initiation Protocol (SIP)

The Session Initiation Protocol or SIP is traditionally used as the security protocol in VoIP infrastructures. It helps us to configure secure sessions between multiple endpoints, which are a part of every VoIP network.

SIP ensures VoIP encryption via SSL, PGP, or S/MIME. However, it still lacks a mechanism for user authentication. This is why it’s extremely important to resolve this vulnerability to prevent identity theft.

Moreover, it also lacks the system to resolve delivery failure between intermediary network devices. The lack of network capabilities makes it difficult for the system to balance load efficiently, something that is problematic for larger enterprises. That said, many companies still use SIP systems for their ability to function interoperability between SIP systems.


Initially, experts designed the H.323 protocol to enable multimedia over IP. It laid the foundation for web-based video conferencing and resolved many of SIP’s call-handling issues. As a result, it was able to reroute calls around failed gateways and ensure that calls don’t get disrupted.

That said, compared to the SIP protocol, H.323 has more security risks. Due to its inability to resolve communication over NAT, it can’t handle data transfer between several networking computers. At the same time, because the H.323 protocol leverages more than one dynamic port across firewalls, the chances of it being attacked through those ports are also greater.


Using any protocols between SIP and H.323 will be a tradeoff between the level of security and the quality of VoIP calls. However, as a user, you need to balance both these issues to create an ideal communication provider for your organization.

This is why it’s best to only trust a VoIP provider with considerable experience. A VoIP service provider can ensure all necessary security measures for your VoIP network and help you implement a secure communication system for your company.

To learn more about how to ramp up security for your office, feel free to follow my blog.