TDM and VOIP

Marin Perez on September 1st, 2006

Testing company Minacom says call quality is increasing for VoIP phone calls, but not for computer-to-computer services like Skype.

VoIP phone services worldwide sound better than the standard public-switched phone network, according to research from Minacom. But, these findings do not apply to PC-to-PC VoIP calling, like Skype, for a variety of issues. The company's data from the last 12 months showed that the quality of VoIP services offered by broadband VoIP providers, cable operators, and telecos has increased , with an average Mean Opinion Score of 4.2, compared to 3.9 for the PSTN. Minacom said, “Based on a MOS threshold of 3.6, only one out of 50 calls in North America were considered to be unacceptable – one in 10 worldwide – while greater than 85 percent of VoIP calls exceeded average PSTN quality of the same period.”

Additionally, VoIP phone calls were found to connect quicker overall, 8.2 seconds on average compared to 8.7 seconds on a PSTN. Minacom's findings did not apply to PC-to-PC VoIP services, like Skype.

The study comes as Brix Networks recently indicated that 1 in 5 Internet phone calls were classified as unacceptable, and that call quality was declining.

“Minacom felt is should be clarified for both those in the VoIP industry, and individuals and enterprises considering VoIP service, that (Brix's) report evaluated computer-to-computer Internet phone service, similar to those offered by Skype, Google Talk, MSN and Yahoo Messenger,” The company said in a written statement. “The quality and service reliability of these applications does not compare to that of the VoIP phone services offered by telecos, cable operators, and broadband VoIP providers who carefully deploy, monitor and manage the the quality of their services.”

“PC-PC VoIP quality is subject to many diverse impairments, including firewall settings, computer performance, antivirus installations, high-compression codecs, and Internet bandwidth shared with gaming, file downloads, Web surfing, and e-mail. By contrast, VoIP offered by service providers is switched using telecom-grade equipment, uses lower-compression codecs, and is prioritized over regular Internet traffic using sophisticated, standards-based multimedia telephone adapters maintained and monitored by the operator.”

VoIP call quality is a very important and sometimes frustrating thing. A report by Telephia showed that more than 27 percent of VoIP subscribers who are likely to change providers do so because of network quality. Adding credence to Minacom's report, J.D. Powers & Associates had their own report which found cable TV providers who offer telephone service ranked higher than traditional phone companies in customer satisfaction.

Still unsure what's all the fuss about VoIP? Please visit here to see if VoIP service is right for you, and here to see 10 questions to ask before you sign a VoIP contract.