Technology

# !/bin/bash
# Linux traffic-shaping occurs on the outbound traffic.  This script
# sets up a virtual interface and places inbound traffic on that virtual
# interface so that it may be rate-limited to simulate a network with a slow inbound connection.
# Removes induced slow-down prior to exiting.  Needs to run as root.

# Physical interface to slow; set as appropriate
oif="wlp2s0"

modprobe ifb numifbs=1
ip link set dev ifb0 up
tc qdisc add dev $oif handle ffff: ingress
tc filter add dev $oif parent ffff: protocol ip u32 match u32 0 0 action mirred egress redirect dev ifb0

tc qdisc add dev ifb0 root handle 1: htb default 10
tc class add dev ifb0 parent 1: classid 1:1 htb rate 1mbit
tc class add dev ifb0 parent 1:1 classid 1:10 htb rate 1mbit

echo "Rate-limiting active.  Hit Control-D to exit."
cat

# shut down rate-limiting
tc qdisc delete dev $oif ingress
tc qdisc delete dev ifb0 root
ip link  set dev ifb0 down
rmmod ifb