http://windtear.net/archives/2005/04/08/000623.html

Bridge - Linux Ethernet bridging
(本文最近于 2006-01-10 11:52 更新)

http://bridge.sourceforge.net/
新主页采用 Wiki 形式 (访问sf会过10s自动跳转)
http://linux-net.osdl.org/index.php/Bridge

下载地址：
http://sourceforge.net/project/showfiles.php?group_id=26089
目前最新版：bridge bridge-utils-1.0.6 March 16, 2005
http://prdownloads.sourceforge.net/bridge/bridge-utils-1.0.6.tar.gz?download

Bridge 网桥
昨天(2005-04-07) 认真去看了一下这个实现
它提供一个 brctl 接口工具
可以方便的把两个接口设为桥接
然后就可以实现二层的连接
连接两个网络 或者vpn 都很有用武之地

Usage: brctl [commands]
commands:
        addbr           <bridge>                add bridge
        delbr           <bridge>                delete bridge
        addif           <bridge> <device>       add interface to bridge
        delif           <bridge> <device>       delete interface from bridge
        setageing       <bridge> <time>         set ageing time
        setbridgeprio   <bridge> <prio>         set bridge priority
        setfd           <bridge> <time>         set bridge forward delay
        sethello        <bridge> <time>         set hello time
        setmaxage       <bridge> <time>         set max message age
        setpathcost     <bridge> <port> <cost>  set path cost
        setportprio     <bridge> <port> <prio>  set port priority
        show                                    show a list of bridges
        showmacs        <bridge>                show a list of mac addrs
        showstp         <bridge>                show bridge stp info
        stp             <bridge> {on|off}       turn stp on/off


新主页信息：
A bridge is a way to connect two Ethernet segments together in a protocol independent way. 
Packets are forwarded based on Ethernet address, rather than IP address (like a router).
Since forwarding is done at Layer 2, all protocols can go transparently through a bridge.
The Linux bridge code implements a subset of the ANSI/IEEE 802.1d standard.
[1].
The original Linux bridging was first done in Linux 2.2, then rewritten by Lennert Buytenhek.
The code for bridging has been integrated into 2.4 and 2.6 kernel series.


原主页信息：
Bridge - Linux Ethernet bridging

Ethernet bridging is a way to connect networks together to form a larger
network.  The standard for bridging is ANSI/IEEE 802.1d which
downloaded from IEEE get 802 site.
A bridge is a way to connect two separate network segments
together in a protocol independent way. Packets are forwarded based
on Ethernet address, rather than IP address (like a router). Since
forwarding is done at Layer 2, all protocols can go transparently
through a bridge.

This site covers the Linux implementation of bridging.
The original Linux bridging was first done in Linux 2.2, then rewritten by
Lennert Buytenhek. The code for bridging has been integrated into
2.4 and 2.6 kernel series.