> 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/fr/quic/quic-0rtt.md).

# 0-RTT

Pour réduire le temps nécessaire à l'établissement d'une nouvelle connexion, un client déjà connecté à un serveur peut mettre en cache certains paramètres de cette connexion et établir une connexion **0-RTT** avec le serveur. Cela permet au client d'envoyer des données immédiatement, sans attendre la fin d'un handshake.


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