> For the complete documentation index, see [llms.txt](https://http3-explained.haxx.se/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://http3-explained.haxx.se/en/the-protocol/feature-tls.md).

# 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.