  The transport layer is ossified. With most of the research and deployment
efforts in the past decade focussing on the Transmission Control Protocol (TCP)
and its extensions, the QUIC standardization by the Internet Engineering Task
Force (IETF) is to be finalized in early 2021. In addition to addressing the
most urgent issues of TCP, QUIC ensures its future extendibility and is
destined to drastically change the transport protocol landscape. In this work,
we present a first look at emerging protocols and their IETF standardization
efforts beyond QUIC v1. While multiple proposed extensions improve on QUIC
itself, Multiplexed Application Substrate over QUIC Encryption (MASQUE) as well
as WebTransport present different approaches to address long-standing problems,
and their interplay extends on QUIC's take to address transport layer
ossification challenges.
