Brix Networks, a company that develops monitoring tools for service providers, analyzed data it gathered from a free Web site it created two years ago called TestYourVoip.com. The site allows consumers to test the quality of their VoIP services. In its study, published Monday, the company discovered that call quality has declined by about 5 percent in the past 18 months.
With almost 1 million VoIP connections tested through its Web site, Brix said that about 20 percent of all calls had unacceptable quality. This is up from about 15 percent of calls made about a year ago.
Kaynam Hedayat, chief technology officer for Brix, said the decline in voice quality is happening because voice services areas other services such as video, music downloads and interactive gaming. IP telephony calls ride over the same network that is also delivering Internet access and in some cases IP-based video. While the speed of broadband networks has increased, consumers are doing more on the Net, which affects call quality, he said.
"The network is ready for VoIP," he said. "But now that there are more services running over the same pipe, carriers need to differentiate packets and prioritize service."
Many Internet companies offering voice services, such as EarthLink, Vonage, Google and Yahoo, are opposed to allowing phone companies or cable operators, which own the underlying broadband networks, to prioritize traffic in order to improve call quality. They fear that network operators will abuse their power by charging unreasonably high fees and eventually squeeze out competing traffic. These companies have been calling for.
But some analysts say the time is quickly approaching when network operators will have to prioritize delay-sensitive traffic such as voice or video.
"Prioritizing traffic is going to have to happen," said Zeus Kerravala, an analyst at the Yankee Group. "The vision for many service providers is to offer video, Internet access and voice on one pipe. And the addition of video is going to be a huge hit on the network. I think consumers will be less tolerant with jittery TV than they have been with voice, so service providers better get the prioritization mechanisms in place today before they try to sell the public on Internet-based video."