> For the complete documentation index, see [llms.txt](https://book.bsdcn.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://book.bsdcn.org/handbook/di-31-zhang-ppp/31.1.-gai-shu.md).

# 31.1.概述

FreeBSD 支持点对点（PPP）协议，可用于通过拨号调制解调器建立网络或互联网连接。本章将介绍如何在 FreeBSD 中配置基于调制解调器的通信服务。

通过阅读本章，你将了解：

* 如何配置、使用和排查 PPP 连接；
* 如何设置以太网上的 PPP（PPPoE）；
* 如何设置异步传输模式上的 PPP（PPPoA）。

在阅读本章之前，你应当：

* 熟悉基本的网络术语；
* 理解拨号连接和 PPP 的基础知识及其用途。


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