The Chaotic Nature of TCP Congestion Control

In this paper we demonstrate how TCP congestion control can show chaotic behavior. We demonstrate the major features of chaotic systems in TCP/IP networks with examples. These features include un- predictability, extreme sensitivity to initial conditions and odd periodicity. Previous work has shown the fractal nature of aggregate TCP/IP traffic and one explanation to this phenomenon was that traffic can be approxi- mated by a large number of ON/OFF sources where the random ON and/or OFF periods are of length described by a heavy tailed distribution. In this paper we show that this argument is not necessary to explain self- similarity, neither randomness is required. Rather, TCP itself as a deter- ministic process creates chaos, which generates self-similarity. This prop- erty is inherent in todays TCP/IP networks and it is independent of higher layer applications or protocols. The two causes: heavy tailed ON/OFF and chaotic TCP together contribute to the phenomena, called fractal nature of Internet traffic. Keywords—TCP congestion control, fractal traffic, chaotic models.