See also WAN-Bridge Network Emulator

Home: http://wanem.sourceforge.net/

Tutorial: http://packetlife.net/blog/2011/jan/12/emulating-wans-wanem/

Tutorial: http://openmaniak.com/wanem.php

WANem is a live-CD Linux distro based on Knoppix available as a .iso file or a virtual machine.

WANem uses routing, not bridging between the client and the server.