HGKeeper

# Skype

This page is a placeholder, for documentation of the Skype protocol used by

Skype.

## Introduction

Some initial work has been done by Efim Bushmanov to reverse engineered the

skype protocol and can be found

[here](http://skype-open-source.blogspot.com/2011/06/skype-protocol-reverse-engineered.html).

Warning: depending on how the developer reverse engineered the protocol (such

as decompiling Skype's binaries) using the documentation may possibly violate

US copyright law and/or the DMCA.

All Skype desktop clients (i.e. Windows, Mac OS X, and Linux) have an

[API](http://developer.skype.com/accessories) which allows other programs

running on the computer to perform Skype actions and receive Skype

notifications on the logged-in Skype account by inter-process communication

with the Skype client. The downsides of this are that 1) you need to have the

Skype client GUI running for this to work, 2) only one account can be logged

into Skype at once (unless you somehow run multiple instances of the Skype

client), and 3) not all features are available in the API.

Skype also offers something called

[SkypeKit](http://developer.skype.com/public/skypekit), which is essentially

the above-mentioned API as a library so you don't have to run a separate Skype

program. With this, [Trillian 5.1 for Windows directly supports native Skype

chat and audio and video calls without running the Skype client](http://blog.trillian.im/?p=2366).

However, there are a lot of legal restrictions on the use of SkypeKit, e.g. you

cannot put it on a mobile device, and you cannot run it on a server.

## Useful Links

* [Wikipedia](http://en.wikipedia.org/wiki/Skype)

* [Some basic descriptions of the Skype protocol](http://www1.cs.columbia.edu/~salman/skype/index.html)

* [a Pidgin plugin that relies on the Skype client](https://code.google.com/p/skype4pidgin/)

* [Skype log file analysis](http://www.docstoc.com/docs/51978646/Skype-Log-File-Analysis)