I've created a bridged network Mac
OS X 10.8.5 using ifconfig and TUNTAP for
OS X to bridge my wireless connection, en0, with a virtual interface, tap0, which I can use for guest VMs:
$ sudo sysctl -w net.inet.ip.forwarding=1
$ sudo sysctl -w net.link.ether.inet.proxyall=1
$ sudo sysctl -w
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