> 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-si-bu-fen-wang-luo-tong-xun.md).

# 第四部分：网络通讯

FreeBSD 是高性能网络服务器上部署最广泛的操作系统之一。本部分的章节包括：

* 串行通信
* PPP 和以太网 PPP（PPPoE）
* 电子邮件
* 运行网络服务器
* 防火墙
* 其他高级网络主题

这些章节供需要时查阅。不需要按特定顺序阅读，也不必在网络环境中使用 FreeBSD 之前阅读所有章节。


---

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