October 2, 2007 -- Keynote Competitive Research, the industry analysis group of Keynote Systems, recently conducted a study of the respective quality of voice services, including Voice over IP (VoIP), packet cable, and traditional phone service (PSTN). According to Keynote, the study reveals that while packet cable digital voice and VoIP offerings still lag in quality, they are proving to be highly competitive with traditional PSTN service providers.
The study benchmarks eight VoIP providers, two packet cable providers, and two PSTN providers, including AT&T CallVantage, AT&T PSTN, Comcast Digital Voice, Primus Lingo, Packet 8, Sun Rocket, Digital Phone from TimeWarner Cable, EarthLink trueVoice, Verizon VoiceWing, Verizon PSTN, Vonage and Vonics Digital. The data for the study was collected over a one month period, from June 1 through June 31, 2007.
The study concludes that VoIP providers still leave room for improvement in important areas including reliability and audio delay. Further, the study notes that only two of the eight voice service providers in the study provided 100% availability. The findings, contends the research firm, are of significance to VoIP providers who are under increasing market pressure to understand and prevent high rates of customer attrition and churn in a rapidly changing market.
In order to benchmark and rank the quality of consumer voice services, Keynote measured the relative performance of the leading voice providers in the New York and San Francisco markets, including digital cable voice services, adapter-based Voice over IP services, and PSTN service in those cities. The research group then rated the leading voice service providers on critical performance factors that influence the end-user experience, using Keynote's commercially available Voice Perspective, an on-demand voice quality test and measurement service.
The study compares VoIP service providers based on reliability and audio clarity over consumer cable modem and DSL network connections, then evaluates network carrier performance on end user perceived call quality. The study evaluates the range of performance between the best voice service providers and the worst. The study also examines variations between prime-time performance and non-prime-time performance of the voice providers, and pinpoints the strengths and weaknesses of each service provider and the voice service technology.
"As VoIP continues to make inroads into business and residential users, customers expect no less than a 'toll quality' voice call. In order to achieve that, service providers will have to continuously monitor the quality of the calls and examine and isolate bottlenecks before they affect customers," says Rajeev Kutty, VoIP product manager at Keynote.
In the study, Keynote placed local and long distance VoIP calls to destination phone numbers on standard (PSTN) phone service. Calls were placed from San Francisco and New York once every 30 minutes for each voice provider and network carrier combination. A total of 125,000 calls were placed over a month-long period. Test calls were compared to traditional phone "toll quality" standards to determine what residential customers can expect when switching from traditional phone lines to VoIP.
To reflect the latest trends in VoIP technology, the new study implements updated voice quality test and measurement methodologies and protocols. Keynote says this type of methodology captures more comprehensive and granular data and strengthens its ability to assess overall VoIP quality. The result, contends the firm, is an accurate representation of the current state of VoIP service quality as perceived by the average consumer of a VoIP service provider.
The Keynote Voice Competitive Research Study is available for purchase from Keynote, and includes detailed results, custom analysis of the data and all raw measurement data. For more information, click here.