Skype has claimed the top spot in the global voice over IP league, according to web traffic analysis by broadband management firm Sandvine.

The data puts the market share in North America for London-based Skype at 46.2 per cent, giving it a clear lead over other VoIP providers including Vonage, AT&T Callvantage and Dialpad, which was acquired by Yahoo last week.

The number two spot is hotly contested between several providers, a spokeswoman for Sandvine told vnunet.com.

Sandvine is a provider of broadband equipment allowing ISPs to give VoIP traffic priority over less time-sensitive data.

It claims that its equipment regulates traffic for over 20 million broadband subscribers worldwide, and 11 million of North America's 60 million subscribers.

Although the comparison between Skype and other VoIP providers is a fair method to identify the balance of power in this nascent market, Skype chief executive Niklas Zennström told vnunet.com in an interview last January that he does not consider Vonage and AT&T as competitors. 

Vonage and AT&T represent a group of VoIP providers that offer a telephone replacement service. Users require a VoIP adapter that they plug into a traditional telephone and hook up to the internet.

Skype develops a software platform for a number of devices, ranging from desktop computers to handhelds and Skype-enabled handsets.

"We are suggesting that Skype is the personal communication service which customers can use in addition to their phone line. What Vonage does is the same as traditional telephony," said Zennström.

"We are offering a personal mobile communications service which comprises IP voice communications, instant messaging and file transfer. Voice communication is part of our offering, but not everything."