# Transport and application

The IETF QUIC protocol is a transport protocol, on top of which other application protocols can be used. The initial application layer protocol is HTTP/3 (h3).

The transport layer supports connections and streams.

The legacy Google version of QUIC had transport and HTTP glued together into one single do-it-all and was a more special-purpose send-http/2-frames-over-udp protocol.


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