SKYPE

Skype (pronounced /ˈskaɪp/) is a software application that allows users to make voice calls over the Internet. Calls to other users within the Skype service are free, while calls to both traditional landline telephones and mobile phone can be made for a fee using a debit-based user account system. Skype has also become popular for its additional features which include instant messaging, file transfer, and video conferencing. The network is operated by Skype Limited, which has its headquarters in Luxembourg and is minority owned by eBay. Most of the development team of Skype is situated in Tallinn, Estonia for cost reasons and outsourced by the Luxembourg parent company^[1]
Some network administrators have banned Skype on corporate,^[2] government, home, and education networks,^[3] citing reasons such as inappropriate usage of resources, excessive bandwidth usage,^[4] and security concerns.^[5]