Bridging Firewall
-=-=-=-=-=-=-=-=-

Patch the kernel with the following patches, available from
http://users.pandora.be/bart.de.schuymer/ebtables/sourcecode.html:
   bridge-nf-0.0.10-against-2.4.20.diff
   ebtables-v2.0.003_vs_2.4.20.diff

Other option is from http://bridge.sourceforge.net/devel/bridge-nf/
(needs more testing)
   bridge-nf-0.0.7-against-2.4.19.diff

Select:
   CONFIG_BRIDGE
   CONFIG_BRIDGE_NF_EBTABLES
   CONFIG_BRIDGE_EBT_* (as needed)

Install bridge-utils on the bridging box

Edit /etc/network/interfaces to have something like:
  auto br0
  iface br0 inet static
        address 203.20.51.131
        netmask 255.255.255.128
        network 203.20.51.128
        broadcast 203.20.51.255
        gateway 203.20.51.129
        bridge_ports all
        up /etc/network/wshaper start
        down /etc/network/wshaper stop

Download the wondershaper from http://lartc.org/wondershaper/,
and put the wshaper script in /etc/network.

For Quality of Service, you need to enable:
   CONFIG_NET_SCHED
   CONFIG_NET_QOS
   CONFIG_NET_ESTIMATOR
   CONFIG_NET_CLS_POLICE

Then pick the queues and classifiers you need - for wondershaper,
you need at least the following:
   CONFIG_NET_SCH_CBQ
   CONFIG_NET_SCH_PRIO
   CONFIG_NET_SCH_SFQ
   CONFIG_NET_SCH_INGRESS
   CONFIG_NET_CLS_U32
   CONFIG_NET_CLS_FW