# TLS 1.3

The transport security used in QUIC is using TLS 1.3 ([RFC 8446](https://tools.ietf.org/html/rfc8446)) and there are never any unencrypted QUIC connections.

TLS 1.3 has several advantages compared to older TLS versions but a primary reason for using it in QUIC is that 1.3 changed the handshake to require fewer roundtrips. It reduces protocol latency.

The Google legacy version of QUIC used a custom crypto.


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