How to deliberately introduce a delay for incoming UDP packets

Question

I want each packet (that match iptables rule) to be delayed by some fixed time interval. How to to this?

Preudocode: iptables -A INPUT -p udp <more conditions> -j DELAY --delay 50000 # delay UDP packets for 50 milliseconds

Update: @related http://superuser.com/questions/147156/simulating-a-low-bandwidth-high-latency-network-connection-on-linux

Answer 1

tc qdisc add dev eth1 root netem delay 250ms hack allows to do it globally for the given interface. It includes UDP packets.