Trouble on the Line

By Richard Hyatt

On February 14, 1876, an inventor from Ohio filed a patent for a device that would transmit voice across telegraph lines. What he didn’t realize was that a mere two hours earlier, another inventor—Alexander Graham Bell—had filed a patent at the same office for the same type of invention. Despite contentions of bribery and theft, Bell, rather than Elisha Gray, is commonly remembered today as the genius behind the telephone.

Neither Gray nor Bell would likely recognize their invention today. In the 130 years since they built their first prototypes, the phone has evolved from the hand-cranked version through Touch Tone dialing and the Princess to the high-tech portable and cordless devices of today. The latest version of telephone communications is called VoIP (Voice over Internet Protocol). It allows users to take advantage of the Internet for phone calls.

Because VoIP communications travel across computer networks, they provide a host of advantages such as flexibility and low cost. Companies must recognize, however, that the networking of telephone communications also creates a new set of risks.

To help you understand the opportunities and the risks VoIP offers, we’ll first review the basics of how networks work and take a look at the challenges that face engineers tasked with building VoIP systems, as well as the tools they use to make this task simpler. We’ll then look at the setup challenges and threats presented by VoIP and examine how these can be addressed.



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