QUIC is a UDP-based multiplexed and secure transport protocol that was standardized in 2021 by the IETF. It seeks to replace the traditional TCP/TLS stack by combining functionality from different layers of the ISO/OSI model. Therefore, it reduces overhead and introduces new functionality to better support application protocols, e.g., streams and datagrams. QUIC is the foundation for HTTP/3 and new proxy technologies (MASQUE). It is used for video streaming and considered for other media services.

This talk will introduce the protocol and motivate its relevance. In the second part, I will provide insights into existing implementations and their performance. Our research shows that QUIC performance varies widely between client and server implementations from 90 Mbit/s to over 6000 Mbit/s. In the second part, I provide an overview about QUIC deployments on the Internet. At least one deployment for 18 different libraries can actually be found on the Internet.

The complexity of the protocol, the diversity of libraries and their usage on the Internet makes QUIC an important research subject.