Dynamic Modeling of Internet tra¢c: Linear versus nonlinear canonical correlation analysis of HTTP versus FTP tra¢c

The Hypertext Transfer Protocol (HTTP) and the File Transfer Protocol (FTP) are both application-level protocols layered over the Transmission Control Protocol (TCP). HTTP is a request/response protocol used for the data transfer over the Internet. The primary function of FTP, on the other hand, is de...ned as transferring ...les e¢ciently and reliably among hosts. We study the statistical and dynamical properties of both HTTP and FTP tra¢c. We use Network Simulator (NS) to generate synthesized data for HTTP and FTP traf...c. We use the Canonical Correlation Analysis (CCA) as our statistical analysis tool. Both Linear Canonical Correlation Analysis (LCCA) and Nonlinear Canonical Correlation Analysis (NLCCA) are used to investigate deterministic, “chaotic,” and stochastic features of the signals. Comparison of linear predictor models and nonlinear predictor models suggests that the tra¢c signals possesses nonlinear features. Finally, NLCCA is implemented in a speci...c way, referred to as Alternating Conditional Expectation (ACE).