How to Secure VOIP Systems

When it comes to voice over IP, progress is a double-edged sword.

The technology offers a host of benefits, from lower calling costs and greater mobility to advanced functions like unified messaging and collaborative whiteboarding. But as VOIP matures, and as hackers become more familiar with its intricacies, the threats may someday equal the benefits—unless companies prepare now.

Today, the biggest VOIP-related security threats are inside a company's firewall. That's because, for the most part, most systems still rely on a combination of an IP network and the PSTN (Public Switched Telephone Network) land-line network. Each time a device engages in a VOIP call, the VOIP phone number's IP address is translated into a standard phone number, which is passed through the PSTN network.

That can be exploited, for example by an employee listening in on a phone call or changing a configuration setting to make the CEO's phone ring at the employee's desk. A malicious user—either a disgruntled employee or a hacker who managed to get inside the building—could launch a DoS (Denial of Service) attack that would flood the network so thoroughly that nobody would be able to make or receive calls.

Read the full story on eWEEK Midmarket.