diff --git a/impl/setup_tundev.sh b/impl/setup_tundev.sh
new file mode 100755
index 0000000..eef4411
--- /dev/null
+++ b/impl/setup_tundev.sh
@@ -0,0 +1,16 @@
+#!/bin/sh
+
+if [ -z "$1" ]; then
+	echo "usage: $0 <device-id>"
+	echo
+	echo "device-id:     Unique number of this device. Will go into the last byte of the IP address."
+	exit 1
+fi
+
+set -euo pipefail
+
+DEV=hamnet70
+
+sudo ip tuntap add dev $DEV mode tun user $(whoami)
+sudo ip link set dev $DEV up
+sudo ip address add dev $DEV 10.99.99.1/24