VoIP Surpassing Standard Call Quality?

Contradicting previous reports to the contrary, Internet and mobile test and measurement company Keynote Systems says that VoIP services outperform landline phone systems in call quality, although the technology still has some ground to make up in other areas such as audio delay.

Twelve VoIP providers were compared in the study including AT&T, Comcast, Lingo, Packet8, Skype, SunRocket, TimeWarner Cable, TrueVoice, Verizon, Vonage, Vonics and Windows Live Messenger. Performance of the services were measured in the New York City and San Francisco markets.

Keynote had studied the VoIP providers once before, releasing its findings in December of last year. The firm found that reliability had improved across the board, and among the top VoIP operators, service was more reliable that traditional phone service.

Additionally, leading operators also fared better in other areas, including audio responsiveness and audio clarity. However, Keynote said there was still room for improvement, as 10 of the 12 surveyed had a score less than that of a toll call over landlines.

Call quality on the average was the same as a GSM cellular phone call, and it was found that call delay increased during peak Internet usage times. This issue was more pronounced on DSL than it was on cable, although Keynote said this did not affect the actual voice quality of the call itself.

This is still a problem, the firm said. "This audio delay can cause callers to talk over each other, leading to conversational disruption and missed information, which can create frustration among users, especially in a business setting," it wrote.

The study was conducted by making nearly 125,000 calls over a one month period. Calls were placed from San Francisco and New York once every 30 minutes on every VoIP provider and network carrier combination.