Today, Skype is one of the most popular proprietary software with closed source code that provides encrypted voice and video communications over the Internet between computers (VoIP) that use peer to peer technology (p2p) and paid services for calls to mobile and landline phones.
As of 2011 Skype has 663 million users worldwide. Skype works on the principle of a black box. The program provides very cool features absolutely free and it makes you wonder about why creators of this program, which is freeware, do not disclose its source code and additionally use various protectors (code visualizers) and impede the analysis of the program through any media. It is quite understandable – free cheese is only in a mousetrap. In this article we will try to explore Skype in an extraordinary and newfangled way namely by means of a dynamic binary instrumentation.