QUIC (HTTP/3) is a modern transport protocol designed to improve performance and security through built in encryption and faster connection setup. However, its design presents new challenges for traditional network security tools such as firewalls and intrusion detection systems, which rely on inspecting unencrypted traffic.

This thesis investigates QUIC’s global adoption and its impact on network visibility. A large scales can of the top 1 million and 10 million domains revealed QUIC support in approximately 38% and 30% of cases, respectively, indicating rapid adoption. Practical tests using pf Sense and Snort showed that these tools can detect QUIC at a transport level but cannot inspect or analyze its contents.

To address this, the study explores emerging solutions such as encrypted traffic analytics and machine learning based fingerprinting. These findings highlight the need for adaptive, privacy aware approaches to security in increasingly encrypted network environments.