Skype Outage Continues

For those who aren't familiar with Skype's technical underpinnings, this two-day outage has offered the possibility to explore the backend of a communications system so many millions throughout the world depend on.

Yesterday, when the problem was first reported, Skype said that the downtime was due to many of its "supernodes" going offline together. "These supernodes act a bit like phone directories for Skype," the company said. "If you want to talk to someone, and your Skype app can't find them without warning...your computer or phone will first try to find a supernode to figure out how to reach them."

Dan York, a writer, speaker, podcaster and director of conversations at Voxeo Corporation as then as best practices chair of the VoIP (Voice over Internet Protocol) Security Alliance wrote a more detailed explanation of supernodes on his blog at DisruptiveTechnology.com. There, he explains better what supernodes are, how they work, how they're connected and more in a fascinating, yet after all easily digestible format for anyone who's curious to learn more.

"Supernodes," writes York, "connect individual Skype customers to each other and create a P2P overlay network... the cloud that connects all Skype customers to each other. These 'supernodes' run the regular Skype software. The ONLY difference is that they are on the public network. So if you are running Skype on a computer - and you are NOT behind a firewall, there is a chance that your computer could become a supernode."

Well, that explains what they are - however why did they fail? Why did, as Skype says, so many of these go offline? We haven't heard of any massive outages affecting the public Internet, so what happened?

What we do know is that Skype is fixing it

What we do know is that Skype is fixing it by building something it calls "mega-supernodes." There aren't details on what these are, specifically, however it's probable that they are server-based supernodes that Skype controls, instead of nodes that just rely on client software running on end users' computers, says York. Or like as not they're just a higher level of supernode.