Skype

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Skype

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What is Skype?

• Proprietary peer to peer internet telephony
  network (VOIP).
• It competes against existing open VOIP protocols
  such as SIP, IAX, and H.323.
• The Skype communications system is notable for
  its broad range of features.

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Software and System

• All Skype traffic is encrypted by default and the
  user cannot turn it off.
• Skype reportedly uses openly available, strong
  encryption algorithms.
• The Skype user directory is entirely
  decentralized and distributed among the nodes in
  the network

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General

• Skype accesses the hard disk several times per
  minute
• Skype is a "complete black box"
• Skype provides an uncontrolled registration
  system for users
• Skype software itself uses a great deal of code
  obfuscation and decryption in memory

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SkypeOut

• It allows skype user to call tradition phones.
• Fees are as low as USD2.142.
• SkypeOut within the USA and Canada to
  destinations within USA and Canada are free.

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Skypepeln

• SkypeIn allows Skype users to receive calls on
  their computers dialed by regular phone
  subscribers .
• This is allowed in Australia, Brazil, Hong Kong
  ,Japan, Most of Europe,and USA.

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Skype voicemail

• Skype Voicemail was released on March 10, 2005.
• Allows callers to leave voice-mail messages for
  Skype users

• Skype Voicemail has experienced numerous
  problems.
• These current problems have not been completely
  resolved.

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Skype video calling

• Skype 2.0 (and above) supports videoconferencing.
• One of the video conferencing solutions between
  Mac and Windows.

• As of 14 Sept. 2006 Skype only supports
  one-to-one video chat.
• They may support multiple point video
  conferencing in the future

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Usage

• Seven million concurrent Skype users were online
  as of August 29, 2006
• Average claimed age 29.7 years old
• About 46 of Skypers are in Europe

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Impact

• Change from traditional network to online
  networks.
• Improved Global Communication
• Lower International rates
• More efficient communication in big corporations

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History

• 2002-2004
• September 2002 Skype Limited received its
  founding investment from Draper Investment
  Company
• April 2003 Skype.com and Skype.net domain names
  registered
• August 2003 First public beta version released
• June 2004 Beta release of version 0.98.0.28 with
  first support for SkypeOut. Credits by voucher
  only initially, then from website.
• July 2004 Release of Version 1.0 for Windows.
• October 2004 1 million Skype users online
  simultaneously

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• 2005
• February 2005 2 million users online
  simultaneouslycitation needed
• March 2005 SkypeIn Public Beta starts. Skype
  reports 1 million SkypeOut users and 29 million
  registered users. 84 million software downloads
  and 5.98 billion talk minutes served. Central
  contact lists introduced with v1.2
• April 2005 Downloaded more than 100 million
  times.
• May 2005 3 million online at once.
  citation needed
• June 2005 Ten billion minutes of voice
  conversation served.
• August 2005 Call forwarding introduced with 1.4
  beta.
• September 2005 SkypeOut banned in South
  China.10 eBay announces purchase of Skype (Sept
  12).
• October 2005 eBay completes purchase of Skype
  (Oct 14).11
• December 2005 videotelephony introduced in
  Skype-to-Skype calls with v2.0 beta

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• 2006
• January 2006 Skype 2.0 released. Five million
  concurrent Skype users on line.
• March 2006 A third party paper analyzing the
  security and methodology of Skype is presented at
  Black Hat Europe 2006.13
• April 2006 100 million registered users.
• May 2006 Skype 2.5 beta introduces Skypecast
  preview and SMS messaging. Skype users spoke for
  6.9 billion minutes during the first quarter
  2006. Skype now handles 7 of the world's
  long-distance minutes.14 Skype for Mac 1.4.0.49
  is released, the first Universal build of Skype.
  First major "free minutes" offer with SkypeOut to
  US and Canadian landlines and mobile phones free
  until December 2006.15

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• June 2006 Skype 2.5 for Windows released. A Mac
  version with video, named Skype for Mac 1.5 Beta,
  is leaked on the Skype site before pulled shortly
  afterwards.
• July 2006 Three new Skype toolbars for Web,
  email, and desktop applications, designed to let
  people initiate voice and video calls, and
  instant messages directly from computer
  applications such as Microsoft Outlook and
  Internet Explorer.16 Skype for Mac 1.5 beta is
  released officially and a preview version with
  Video is also released for Mac.17
• August 2006 Skype for Windows 2.6 early preview
  is released.18 Seven million concurrent users
  online. citation needed
• September 2006 Skype launches free SkypeOut calls
  from France to landlines in France.19
• October 2006 Skype 2.0 for Mac is released, the
  first full release of Skype for Macintosh