Is Encrypted ClientHello a Challenge for Traffic Classification?

Although the widely-used Transport Layer Security (TLS) protocol hides application data, an unencrypted part of TLS handshake, specifically server name indication (SNI), is a backdoor for encrypted traffic classification frameworks. The recently developed Encrypted ClientHello (ECH) amendment to aims protect privacy-sensitive content message, including SNI. Conversely, ECH can be game-changer in early detection traffic. paper shows that performance state-of-the-art algorithms degrades significantly with introduction ECH. Hence, novel approaches real-time are required. develops two address this challenge. first one uses bytes Hello messages as independent features Random Forest algorithm. It extremely lightweight and suits throughput-focused classification. faster than by three times achieves higher quality. second algorithm augments approach focusing on particular metadata handshake. This way, it efficiently extracts data from exchange highest quality all considered scenarios. has lower error rate provides reliable