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Is VoIP Secure Enough For Prime Time?

VoIP is hot, but VoIP security is not. Security risks abound in current commercial VoIP solutions, including Denial of Service (DoS) attacks, eavesdropping, and a host of new vectors for intrusion and malware propagation. As it stands now, the benefits of VoIP--cheaper phone bills and converged voice and data applications--may not be worth the risks.


When you migrate voice from a circuit-switched medium to a packet-switched one, you expose that voice traffic to a pair of serious security risks: DoS attacks and eavesdropping.

Unlike traditional uses of IP networks (think downloading files), VoIP is ultrasensitive to latency. Seemingly small delays of 150ms can transform a high-quality call into unintelligible gobbledygook. Jitter, a phenomenon where network-induced delays cause packets to arrive out of sequence, can also be problematic. Losing a single packet isn't a big deal because VoIP packets are small and contain only 12 to 62ms worth of data. But packet loss as low as 1 percent can make a call hard to understand, and a 5 percent loss turns VoIP into toast.

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