Skype brings 10 million users back online, but millions more still without call service

Luxembourg internet phone company Skype said this morning that users had doubled in several hours to 10 million people, though the impact on investor sentiment may be more lasting.

Skype was rapidly bringing its calling service back online today after a software problem arose Wednesday that disconnected millions of families, friends, colleagues, and businesses just days before Christmas.

The Luxembourg company said 5 million people were using Skype early Thursday morning, about 30 percent of normal for that time of day. Two hours later, in a Twitter post at 9:30 a.m. EST, Skype said the number of online users had doubled to 10 million over the previous hour.

"Unfortunately, it’s not possible for us to predict on an individual level when you’ll be able to sign in again, and we thank you for your patience in the meantime," the company, which has some 125 million subscribers and up to 23 million simultaneous users at peak times, said in a blog post today.

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Skype has become a famous global brand since launching in 2003 and connecting the world with its free Skype-to-Skype voice and video calls and cheap Skype-to-phone calls. TeleGeography Research found that Skype-to-Skype calls accounted for 13 percent of all international call minutes in 2009, up from 8 percent in 2008, making it the largest provider of cross border communications in the world. But the latest technical malfunction – at Christmastime, no less – may dampen investor excitement about Skype's forthcoming initial public offering (IPO).

"The outage comes at a time when Skype is starting to ask larger corporations for their business," industry commentator Om Malik told the BBC. "If I am a big business, I would be extremely cautious about adopting Skype for business, especially in light of this current outage."

Igor Hnatko told the British news service that his Malaysia-based outsourcing company had been "severely affected." "It had made me realize to what extent my business is dependent on VOIP technology and Skype as a solution to keeping in touch with clients, and employees."

The problem, according to the company, is with its "supernodes." A supernode is a computer that acts something like a phone directory, Skype explained, aggregating traffic and rerouting it worldwide. For example, if you are logging onto Skype from your mobile phone while a friend is logging onto Skype from a laptop computer, then a supernode helps bridge the communication line between phone and computer.

"Under normal circumstances, there are a large number of supernodes available," Skype explained in a blog post. "Unfortunately, today, many of them were taken offline by a problem affecting some versions of Skype."

Skype said it was creating "mega-supernodes" to solve the problem. Engineers restored some services overnight, allowing millions of people to today use the online calling service but still causing troubles for millions more.

"Please note that some features may not work as reliably as expected – peoples’ online status may be slow to update, and instant messages might not be delivered as quickly as they are normally. Group video calling will take longer to return to normal," the company said in a separate posting on its blog.

In the first half of 2010, according to the company's website, Skype users made 6.4 billion minutes of calls to landlines and mobiles phones, along with 88.4 billion minutes of Skype-to-Skype calls (approximately 40 percent of these were video calls).

Skype's last significant outage was in 2007, when users lost access to the network for between 12 hours and two days, according to the Monitor.

Keep updated via Skype's Twitter feed.

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