# QUIC之上的HTTP协议

HTTP层以HTTP风格传输内容，包括使用QPACK进行HTTP头部压缩——这和HTTP/2中使用HPACK压缩头部类似。

HPACK算法依赖于数据流的有序交付，由于HTTP/3的数据流之间可能乱序，所以该算法需要修改才能使用。QPACK可被视作适用于QUIC版本的[HPACK](https://httpwg.org/specs/rfc7541.html)。


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