A review on machine learning–based approaches for Internet traffic classification

Traffic classification acquired the interest of the Internet community early on. Different approaches have been proposed to classify Internet traffic to manage both security and Quality of Service (QoS). However, traditional classification approaches consisting of modifying the Transmission Control Protocol/Internet Protocol (TCP/IP) scheme have not been adopted due to their complex management. In addition, port-based methods and deep packet inspection have limitations in dealing with new traffic characteristics (e.g., dynamic port allocation, tunneling, encryption). Conversely, machine learning (ML) solutions effectively classify traffic down to the device type and specific user action. Another research direction aims to anonymize Internet traffic and thwart classification to maintain user privacy. Existing traffic surveys focus on classification and do not consider anonymization. Here, we review the Internet traffic classification and obfuscation techniques, largely considering the ML-based solutions. In addition, this paper presents a comprehensive review of various data representation methods, and the different objectives of Internet traffic classification. Finally, we present the key findings, limitations, and recommendations for future research.