# 协议特点

本章从高层次出发概述QUIC协议。

下图是使用HTTP传输时，HTTP/2（左）和HTTP/3（右）的协议栈对比。

![QUIC logo](/files/-LvW35eBvHx2Ix3BXNhl)


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://http3-explained.haxx.se/zh/the-protocol.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.