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How to Enhance the Security of Your VOIP Connection

The use of Voice Over Internet Protocol (VOIP) for communication is a recent technology that has attracted quite some interest from individuals, BPO companies, and corporate entities, owing to its ease of use and affordability. Its rich bandwidth, better hardware and enhanced software are some of its strong points, offering lower phone bills, better management and express operation.


The plain old telephone service (POTS) was costly, inefficient and managed only by a few companies. Little wonder then why more and more people are going for VOIP communication to replace their PBX systems.

Sadly though, just like every other new technology, VOIP comes with its security challenges. Data spoken over VOIP is as vulnerable to cyber attack as data sent via text, and these facts are not exactly noticeable to new users. An attacker could infiltrate your signaling server and create tracks of your calls over your network.

Your VOIP gateway could also be breached to gain access to your conversations. Perhaps more worrisome is the man-in-the-middle attack, where your call parameters could be intercepted and modified. Such attacks are used in redirection of calls and identity theft.

At the core of the VOIP technology are computers with software, though they tend to act as phones. Software vulnerability also poses security threat since they are prone to malicious bugs. With all the threats outlined above and some more, it is imperative to enhance security of your VOIP connection. This article intends to show you just how to increase VOIP security.

  • Encryption

    Encrypting your VOIP data makes it safe from interception over the internet or corporate intranets. You can do that by subscribing to a VPN service, since only very few commercial VOIP providers actually encrypt their data. A VPN can encrypt voice traffic and reduce susceptibility to capture and replay.

    A VPN also comes into play when you are considering authenticating remote sites to ensure communication from reliable sources. A major cause of concern with using a VPN for encryption is latency. VOIP encryption causes a delay which can result in some issues. The delay extends with the strength of encryption method. This can, however, be managed with the use of a VPN accelerator, which passes the encryption processing to another CPU.

    You can also use dedicated VPN channels to separate voice data transfer from other data traffic. With this, you can control QoS.

  • Secure Server Configuration

    The security of your server setup should also be given close attention. It is advisable to make sure your VOIP equipment are based on the best security infrastructure such as WPA2 and IEE 802.11i.

    Separating your VOIP connection from your standard internet connectivity further ensures your VOIP security. You may also want to block ports that are not necessary for your VOIP configuration, and avoid calls to locations whose security status are not guaranteed.

  • Use of Firewall

    You can also take advantage of special firewalls to enhance security of your VOIP connection. These firewalls and anti-viruses ensure your VOIP equipment is not hacked, by checking unsafe applications and detecting abnormal patterns in your VOIP traffic.

    As a result, your device is safe from DOS attacks and data sniffing. Keep your antivirus, as well as your OS updated to the latest versions.

  • Authentication

    We had mentioned earlier that you could use a VPN to enforce authentication of remote sites to ensure trusted communication. You can further enhance security of your VOIP connection by making sure that users provide their unique credentials before they are can be permitted to place calls on VOIP.

    Moreover, it is wise to change the usernames and passwords given to you by default from your VOIP service provider. This reduces the chances of hackers compromising your VOIP server to make unauthorized calls. Passwords should be chosen carefully, so they cannot be guessed.


VOIP is increasingly becoming relevant in intranet and internet communications, due to its efficiency and lower cost. However, you have a duty to increase your VOIP security to avoid being a victim of unpleasant attacks.

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