A network without a firewall is like a gated home compound without a fence. Without a fence, you will not be able to monitor and control people getting into and out of your home compound. Like a fence does to the home compound, a firewall (which is basically a network security system), monitors and controls incoming as well as outgoing network traffic grounded on programmed security rules. In other words, a firewall acts as a wall between a trusted internal network and untrusted external network.

VoIP phone services require that you use remote extensions. Also, you may want to host your VoIP phone system on one the of the cloud solution providers’ platforms. This will require you to make some changes to your firewall configuration in order to allow your phone system to communicate effectively and securely with the SIP trunks and remote VoIP phones. This is what is referred to as VoIP firewall configuration.

Why VoIP Firewall Configuration important?

VoIP phone system utilizes Real-time Transport Protocol (RTP) and IETF Session Initiation Protocol (SIP) for call signaling as well as voice-message transfer. These, plus their related control protocols, do not offer satisfactory call-party verification, end-to-end integrity encryption and confidentiality procedures on call signaling and call data like the media streams comprising compacted and encrypted speech. Therefore, without the establishment and implementation of the VoIP firewall configuration, attackers have many paths to use in posing security attacks.

Most security threats target VoIP endpoints. Also, the cyber fraudsters want to gain unauthorized access to the operating systems, Internet protocols, applications and management interfaces of VoIP hard phones and computers running softphones. The VoIP system is also exposed to malicious viruses, worms, and many denial-of-service (DoS) attacks that manipulate common Internet protocols and VoIP protocols themselves.

VoIP firewall configuration is an important milestone in the implementation of the VoIP phone system in your business. This is because of the following reasons:

Checks traffic

VoIP firewall configuration ensures that the VoIP inflow and outflow traffic is tracked. The firewall will be able to investigate the packets of data, getting into and out of the phone system, to determine if there’s hazardous information that might jeopardize your network’s security. This will also help your business to better utilize the available network capacity.

Stops Trojan horses

With so many remote phones, and sometimes sharing of the network with other businesses, there is a possibility of Trojan horses silently transmitting your confidential information to a web server which may later lead to misbehaving of computers in your network. Firewall configuration will help block these Trojan horses.

Obstructs hackers

Firewall configuration will block hackers from accessing computers under your network. Hackers prefer concealing their identity when conducting illicit online activities like spreading of viruses.

Prevents keyloggers

A keylogger is spyware software that cyber fraudsters attempt to install on your computer networks so that they can learn your employees’ keystrokes process which can, in turn, help them log into your private online accounts. VoIP firewall configuration will minimize the keyloggers’ risk.

Avoid spamming

Spam often conceals spyware and remote administration tools. Also, spam over VoIP can carry unwanted sales calls and other irritating messages. In addition, programs downloaded to softphones could include unseen malware.

Impersonation attacks

Insider attacks are more rampant than outsider attacks. Some employees are likely to misuse the network. Configuring the VoIP firewall will help detect abuse and identify perpetrators.

How does VoIP Firewall Configuration happen?

A typical VoIP firewall configuration includes the following steps:

  • Step 1: Configure the ports for your SIP trunk or VoIP provider
  • Step 2: Configure the ports for remote VoIP Apps
  • Step 3: Configuration ports for remote IP Phones or bridges via direct SIP
  • Step 4: Port configuration for WebMeeting, SMTP & Activation
  • Step 5: Disable SIP ALG
  • Step 6: Do the VoIP Firewall test
  • Step 7: Implement

The VoIP firewall configuration is a high-tech operation. Your IT administrators should establish firewalls that can spot and respond to SIP signaling messages, and that can process RTP media streams without adding significant latency. To successfully execute this process, it will need a team with a proven methodology and extensive experience. Make sure of professional implementation services such as 8X8 Elite Touch Implementation to configure your VoIP firewall.


When it comes to VoIP, 8x8 provides a reliable and compliant cloud solution at a demanding level rarely seen by other cloud providers. Don't take your chances with a subpar cloud-based telecom system. Call 1-866-879-8647 or fill out an online form to request a no-obligation quote from an 8x8 product specialist.


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