Telephone Call Route Fingerprinting

by Jago Maniscalchi // October 18, 2010 // News // No comments

Security researchers in the States say they have developed a cunning new method of “fingerprinting” voice calls that could offer a route to trustworthy caller ID and a barrier against so-called “vishing” or voice phishing.

The tool is called PinDr0p, and works by analysing the various characteristic noise artifacts left in audio by the different types of voice network – cellular, VoIP etc. For instance, packet loss leaves tiny gaps in audio signals, too brief for the human ear to detect, but quite perceptible to the PinDr0p algorithms. Vishers and others wishing to avoid giving away the origin of a call will often route a call through multiple different network types.

“There’s a joke: ‘On the Internet, no one knows you’re a dog’. Now that’s moving to phones,” says Mustaque Ahamad of the Georgia Institute of Technology. “The need is obvious to build security into these voice systems … PinDr0p needs no additional detection infrastructure; all it uses is the sound you hear on the phone.”

About the Author

Jago Maniscalchi is a Cyber security consultant, though he tries to avoid the word "Cyber" at all costs. He has spent 15 years working with Information Systems and has experience in website hosting, software engineering, infrastructure management, data analysis and security assessment. Jago lives in London with his family, enough pets to start a small zooalogical society, and a Samsung NaviBot Robotic Vacuum Cleaner. Despite an aptitude for learning computer languages, his repeated attempts to learn Italian have resulted in spectacular failure.