URL: http://www2.net.in.tum.de/~anja/feldmann/papers/imc03.pdf Entry Dates: 2009-02-06 Abstract: In our quest to better understand network traffic dynamics, we examine Internet chat systems. Although chat as an application does not contribute huge amounts of traffic, chat systems are known to be habit-forming. This implies that catering to such users can be a promising way of attracting them, especially in low bandwidth environments such as wireless networks. Unfortunately there is no common protocol base for chat systems. Rather there are a multitude of protocol variants whose specifications, with some exceptions, such as IRC and ICQ, are unavailable or ill defined. In addition, chat systems are often layered on top of other application protocols like HTTP. Therefore there is no simple way of even identifying chat traffic. In this paper we show how to separate chat traffic from other Internet traffic and present the results of an extensive validation of our methodology. Using our methodology we gather a week long trace of all chat traffic that crosses a 155 Mbit/s link from the Saarland University to the Internet and present an initial characterization. Results: