An error in some versions of Skype s software client is to blame for the 24 hour outage last week. The company is working to prevent future outages by bolstering their automatic update system with more frequent hotfixs. Skype introduced hundreds of instances of Skype software into the P2P network to act as supernodes and provide the. capacity to accelerate the recovery. This process was repeated until the system was completely restored on December 24. The company said it is taking steps to prevent further outages.
Source: https://threatpost.com/skype-client-error-causes-global-outage-122910/74808/