Bruce Davie makes an excellent point in his QUIC Is Not a TCP Replacement article – QUIC not a next-generation TCP, it’s a reliable RPC transport protocol.

What Bruce forgot to mention is that we had a production-grade RPC transport protocol for years – SCTP (Stream Control Transmission Protocol) – but it had two shortcomings:

• It wasn’t invented by the right people;
• It used a different IP protocol number and thus upset every ossified middlebox in the Internet. QUIC hides on top of UDP (because adding extra headers makes at least as much sense as junk DNA).