Internet phone and video service Skype went down in a global service outage today, underscoring a weakness of the free online communication tool.
Skype, partly owned by Web retailer eBay, said some users were having problems signing on. Users in Asia and Europe complained of the outage on social network site Twitter.
Representatives from the seven-year-old company apologised and explained the cause of the outage on the company's blog.
The outage was caused by the failure of what Skype terms "supernodes" - computers that "act like phone directories for Skype."
"Skype isn’t a network like a conventional phone or IM network – instead, it relies on millions of individual connections between computers and phones to keep things up and running. Some of these computers are what we call ‘supernodes’. If you want to talk to someone, and your Skype app can’t find them immediately (for example, because they’re connecting from a different location or from a different device) your computer or phone will first try to find a supernode to figure out how to reach them," the company said on its blog.
"Under normal circumstances, there are a large number of supernodes available. Unfortunately, today, many of them were taken offline by a problem affecting some versions of Skype. As Skype relies on being able to maintain contact with supernodes, it may appear offline for some of you."
Skype said its engineers were working on creating new ‘mega-supernodes’ to make up for those supernodes offline.
"Some features, like group video calling, may take longer to return to normal," the company said.
The company said enterprise customers should be unaffected aside from delays signing in.
Dropped calls and service quality have long been seen as a weak point for Skype, which offers free voice and video services between users as well as low-cost calls to landlines. It now faces competition from rival online phone providers such as Google, which lets its users make calls through their Gmail accounts.
Skype is expecting to raise up to US$1 billion in an initial public offering, sources familiar with the matter told Reuters last month. One source has said the IPO will likely come some time next year.
Skype was founded in 2003. Online auction and e-commerce website eBay bought it in 2005 for US$3.1 billion.
In November, eBay sold a majority stake to an investor group including Silver Lake, Canada Pension Plan Investment Board and Andreessen Horowitz for US$1.9 billion in cash and a US$125 million note. EBay retained a 30 percent stake.
(Reporting by Brett Winterford and Ritsuko Ando. Editing by Robert MacMillan)