added Eyke's LabView interface

clients/README.md

 # S2SS clients
 
-This directory contains code and projects to connect
-various simulators and tools to the S2SS server.
-
-Author: Steffen Vogel <steffen.vogel@rwth-aachen.de>
-Date: Mid 2014 - End 2015
+This directory contains code and projects to connect various simulators and tools to the S2SS server.
+Usually, this are projects which are not based on the S2SS source code but which are using the same protocol as defined by the `socket` node-type.
+For a protocol specification, please see `include/msg_format.h`.
 
 - opal/udp
    Contains the implementation of an asynchronous process block for RT-LAB.
-   This block allows exchanging messages with an S2SS server over UDP/TCP.
+   This block allows exchanging sample values with S2SS over UDP using the `socket` node-type.
+   Author: Steffen Vogel <stvogel@eonerc.rwth-aachen.de>
+
+- labview
+   This example model is using LabView standard UDP blocks to exchange sample values with S2SS over UDP using the `socket` node-type.
+   Author: Eyke Liegmann <ELiegmann@eonerc.rwth-aachen.de>

tools/tc/tc-netem2.sh

+#!/bin/bash
+#
+# Transparent Network Emulation Proxy for Layer 2 & 3
+#
+# Dependencies: iptables, ebtables and iproute2
+#
+# Author: Steffen Vogel <post@steffenvogel.de>
+
+set -e # Abort on error
+die() { echo "$1"; exit -1; }
+
+# Apply netem qdisc also for reverse path
+REVERSE=0
+
+# This scripts also supports L3 IP packets. Simply replace the MAC by IP addresses
+LAYER=2
+
+SRC=00:50:C2:4F:92:D5
+DST=00:50:C2:4F:92:D6
+
+#DST=01:0C:CD:01:01:FF
+MY=$SRC
+
+SRC_IF=p5p1.10
+DST_IF=p5p1.11
+
+# Network emulation settings (see http://stuff.onse.fi/man?program=tc-netem&section=8)
+NETEM="delay 1000000 20000 distribution normal duplicate 4 loss 20"
+
+##############################################################################################
+# Do not change something below this line!
+
+MARK=$RANDOM
+
+# Tools
+TC=/sbin/tc
+if   [ "$LAYER" -eq "2" ]; then
+	NF=/sbin/ebtables
+elif [ "$LAYER" -eq "3" ]; then
+	NF=/sbin/iptables
+fi
+
+# Test permissions
+(( $(id -u) == 0 )) || die "This script must be executed as root (run: sudo $0)"
+
+# Test if tools are available
+[ -x $NF ] || die "Please install $NF (run: sudo apt-get install ebtables iptables)"
+[ -x $TC ] || die "Please install $TC (run: sudo apt-get install iproute2)"
+
+# Load kernel modules
+modprobe sch_netem || die "The netem qdisc is not compiled in this kernel!"
+
+# Clear tables and chains to get a clean state
+$NF -t nat -F
+$NF -t nat -X
+
+exit
+
+# Add new chain, mark packets from $SRC and redirect them to $DEST
+
+# Insert new chain into flow
+$NF -t nat -A PREROUTING -i $SRC_IF -s $SRC -j mark --mark-set $MARK --mark-target CONTINUE
+$NF -t nat -A PREROUTING -i $SRC_IF -s $SRC -j dnat --to-dst $DST --dnat-target ACCEPT
+
+$NF -t nat -A PREROUTING -i $DST_IF -s $DST -j mark --mark-set $MARK --mark-target CONTINUE
+$NF -t nat -A PREROUTING -i $DST_IF -s $DST -j dnat --to-dst $SRC --dnat-target ACCEPT
+
+exit
+
+# Clean traffic control
+$TC qdisc delete dev $DST_IF root || true
+
+# Add classful qdisc to egress (outgoing) network device
+$TC qdisc  replace dev $DST_IF root handle 4000 prio bands 4 priomap 1 2 2 2 1 2 0 0 1 1 1 1 1 1 1 1
+$TC qdisc  add     dev $DST_IF parent 4000:4 handle 4020 netem $NETEM
+$TC filter add     dev $DST_IF protocol ip handle $MARK fw flowid 4000:4
+
+echo -e "Successfully configured network emulation:"
+
+echo -e "Netem Settings for $SRC ($SRC_IF) => $DST ($DST_IF):"
+echo -e "   $NETEM"
+if (( $REVERSE )); then
+	echo -e "Netem Settings for $DST ($DST_IF) => $SRC ($SRC_IF):"
+	echo -e "   $NETEM_REV"
+fi
+
+if [ -n $DEBUG ]; then
+	if [ "$SRC_IF" == "$DST_IF" ]; then
+		IFNS="$SRC_IF"
+	else
+		IFNS="$SRC_IF $DST_IF"
+	fi
+
+	for inf in $IFNS; do
+		for cmd in qdisc filter class; do
+			echo -e "\nTC ==> $if: $cmd"
+			tc -d -p $cmd show dev $inf
+		done
+	done
+
+	echo -e "\nTABLES ==>"
+	$NF -t nat -L
+fi