> 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/zh/proc/proc-h2.md).

# HTTP/2的经验

HTTP/2规范RFC 7540发布于2015年5月，只比QUIC首次进入IETF早一个月。

HTTP/2的发布为HTTP进化奠定了基础，同时这让HTTP/2工作组认识到迭代更新的HTTP版本会比从第一版到第二版（花费约16年）快得多。

随着HTTP/2的发布，用户和软件堆栈不再假设HTTP是一个序列化的、基于文本的协议。

HTTP-over-QUIC(HTTP/3)建立在HTTP/2的基础上，并从中借鉴了许多概念。由于某些具体的概念已被QUIC所涵盖，所以从HTTP层中移除。


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