> For the complete documentation index, see [llms.txt](https://docs.console.zenlayer.com/welcome/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.console.zenlayer.com/welcome/cn/glossary/u-z/u.md).

# U

## UDP

UDP 是用户数据报协议（User Datagram Protocol）的缩写，它是一种在互联网协议（IP）层上运行的无连接传输协议。与 TCP 不同，UDP 不提供数据传输的保证、排序或流量控制机制。相反，UDP 提供了一种简单且轻量的方式在网络上发送和接收数据报（即数据包）。UDP 常用于需要低延迟通信或能够容忍一定程度数据丢失的应用，例如在线游戏、视频流和实时通信应用。它还用于需要组播或多播通信的应用，其中单个数据包可以同时发送给多个接收者。UDP 数据包的发送无需在发送方和接收方之间建立连接。发送方只需将数据报发送到特定的目的地 IP 地址和端口号。数据包可能会丢失或接收顺序错乱，但接收方不会向发送方通知任何错误或丢失的数据包。由于 UDP 不提供任何流量控制或拥塞控制机制，对于需要快速、低延迟通信的应用，它的速度可能比 TCP 更快。然而，这也意味着 UDP 可能不如 TCP 可靠，并且可能需要额外的错误检测和纠正机制来确保数据正确接收。


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## 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, and the optional `goal` query parameter:

```
GET https://docs.console.zenlayer.com/welcome/cn/glossary/u-z/u.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

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.