VoIP Closes the Quality Gap

A new study by Minacom, a supplier of service level test automation systems for telephone companies, finds that the quality of voice over IP (VoIP) service markedly improved over the last twelve months, and is now regularly exceeding the quality of “basic dial tone” services, also know as public switched telephone network (PSTN) calling. John Williamson, editor of U.K.-based telecom site Telecom Redux, provided a summary of Minacom’s findings.

“According to data collected over the last 12 months by Minacom’s standards-based, single-ended service quality test system, VoIP service quality increased steadily, with an average Mean Opinion Score (MOS) of 4.2, compared to 3.9 for the PSTN (MOS is a scale commonly used to describe speech quality, ranging from 1 (worst) to 5 (best)). “Based on a MOS threshold of 3.6, only 1 out of 50 calls in North America were considered to be unacceptable – 1 in 10 worldwide – while greater than 85% of VoIP calls exceeded average PSTN quality over the same period. Detailed results apparently show that VoIP service bettered PSTN quality worldwide, and improved in all regions over the course of the survey. In addition to superior sound quality, calls over VoIP connected quicker overall – 8.2 seconds on average, compared to 8.9 seconds for those placed over the PSTN. Regionally, the PSTN was faster to connect for calls placed to North America (4.3 seconds versus 5.7 for VoIP), while international calls connected faster with VoIP (8.7 versus 10.4 seconds for PSTN). Linear regression indicates that VoIP is closing the gap, connecting 2 seconds faster in July 2006 than a year earlier.”

Williamson notes the Minacom findings rebut and clarify an earlier study from Brix Networks that slammed VoIP quality. The Brix study, it turns out, included PC-to-PC calls, which Minacom notes are indeed of lower quality, as part of the VoIP group. The Minacom study was limited to VoIP services, such as Vonage and AT&T CallVantage, that use conventional telephone sets. As VoIP quality improves, regulators will be hard-pressed to justify continued subsidies and rate caps for PSTN service, which they still tend to regard as the “gold standard” of service whose affordability needs to be preserved. They ignore market data shows that people of all ages and incomes are rejecting PSTN service, because in reality, when compared to wireless or VoIP, PSTN is the least attractive choice. It’s tethered to one location and offers none of the additional features (call forwarding, caller ID, voicemail, etc.) that come free with newer services. At the same time, for service providers, PSTN is the most expensive service to provision. Until now, regulators did have the quality card to play. That ace is turning out to be a deuce. Nonetheless, recent legislation to remove price caps on “basic service” in California and North Carolina have come under fire from consumer advocates, even though their elimination would stimulate migration to cheaper, more robust calling services, not to mention more investment and competitive entry in a segment that the publicââ?¬â??backed now by hard dataââ?¬â??sees as clearly superior.