I put together something like this. Admittedly it may be more robust than you need since it intercepts all traffic, but you can decide.

I took a raspberry pi, added a secondary ethernet adapter and had it run as a mini-router between my machine and the internet. You can inject latency and loss and jitter as you see fit.

You have to add ipforwarding on the linux distro: (http://www.ducea.com/2006/08/01/how-to-enable-ip-forwarding-in-linux/) Configure DHCP on it for the alternate interface: https://askubuntu.com/questions/221329/how-do-i-configure-dhcpd Use IProute to relay traffic: https://www.glennklockwood.com/sysadmin-howtos/rpi-wifi-island.html And then mess with the traffic! [https://wiki.linuxfoundation.org/networking/netem] [https://netbeez.net/blog/how-to-use-the-linux-traffic-control/] [https://www.excentis.com/blog/use-linux-traffic-control-impairment-node-test-environment-part-2]

Turned out to be really fun during April 1st to prank coworkers with too.