diff --git a/SIGCOMM_2015/.gitignore b/SIGCOMM_2015/.gitignore
new file mode 100644
index 0000000..b4889e1
--- /dev/null
+++ b/SIGCOMM_2015/.gitignore
@@ -0,0 +1,13 @@
+# Python byte code
+*.pyc
+
+# Emacs
+*~
+
+# Compiled JSON
+*.json
+
+*.pcap
+
+# Extracted solutions
+solution/
\ No newline at end of file
diff --git a/SIGCOMM_2015/env.sh b/SIGCOMM_2015/env.sh
new file mode 100644
index 0000000..cc958e4
--- /dev/null
+++ b/SIGCOMM_2015/env.sh
@@ -0,0 +1,8 @@
+THIS_DIR=$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )
+
+# ---------------- EDIT THIS ------------------
+BMV2_PATH=$THIS_DIR/../../bmv2
+# e.g. BMV2_PATH=$THIS_DIR/../bmv2
+P4C_BM_PATH=$THIS_DIR/../../p4c-bm
+# e.g P4C_BM_PATH=$THIS_DIR/../p4c-bm
+# ---------------- END ------------------
diff --git a/SIGCOMM_2015/source_routing/cleanup b/SIGCOMM_2015/source_routing/cleanup
new file mode 100755
index 0000000..4035587
--- /dev/null
+++ b/SIGCOMM_2015/source_routing/cleanup
@@ -0,0 +1,2 @@
+sudo killall simple_switch
+redis-cli FLUSHDB
\ No newline at end of file
diff --git a/SIGCOMM_2015/source_routing/commands.txt b/SIGCOMM_2015/source_routing/commands.txt
new file mode 100644
index 0000000..e69de29
diff --git a/SIGCOMM_2015/source_routing/p4src/source_routing.p4 b/SIGCOMM_2015/source_routing/p4src/source_routing.p4
new file mode 100644
index 0000000..04fcd9e
--- /dev/null
+++ b/SIGCOMM_2015/source_routing/p4src/source_routing.p4
@@ -0,0 +1,28 @@
+/*
+Copyright 2013-present Barefoot Networks, Inc. 
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+parser start {
+    // TODO
+    return ingress;
+}
+
+control ingress {
+    // TODO
+}
+
+control egress {
+    // leave empty
+}
diff --git a/SIGCOMM_2015/source_routing/receive.py b/SIGCOMM_2015/source_routing/receive.py
new file mode 100755
index 0000000..40fefac
--- /dev/null
+++ b/SIGCOMM_2015/source_routing/receive.py
@@ -0,0 +1,42 @@
+#!/usr/bin/python
+
+# Copyright 2013-present Barefoot Networks, Inc. 
+# 
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+# 
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from scapy.all import sniff, sendp
+from scapy.all import Packet
+from scapy.all import ShortField, IntField, LongField, BitField
+
+import sys
+import struct
+
+def handle_pkt(pkt):
+    pkt = str(pkt)
+    if len(pkt) < 12: return
+    preamble = pkt[:8]
+    preamble_exp = "\x00" * 8
+    if preamble != preamble_exp: return
+    num_valid = struct.unpack("<L", pkt[8:12])[0]
+    if num_valid != 0:
+        print "received incorrect packet"
+    msg = pkt[12:]
+    print msg
+    sys.stdout.flush()
+
+def main():
+    sniff(iface = "eth0",
+          prn = lambda x: handle_pkt(x))
+
+if __name__ == '__main__':
+    main()
diff --git a/SIGCOMM_2015/source_routing/run_demo.sh b/SIGCOMM_2015/source_routing/run_demo.sh
new file mode 100755
index 0000000..bc2f639
--- /dev/null
+++ b/SIGCOMM_2015/source_routing/run_demo.sh
@@ -0,0 +1,31 @@
+#!/bin/bash
+
+# Copyright 2013-present Barefoot Networks, Inc. 
+# 
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+# 
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+THIS_DIR=$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )
+
+source $THIS_DIR/../env.sh
+
+P4C_BM_SCRIPT=$P4C_BM_PATH/p4c_bm/__main__.py
+
+SWITCH_PATH=$BMV2_PATH/targets/simple_switch/simple_switch
+
+CLI_PATH=$BMV2_PATH/tools/runtime_CLI.py
+
+$P4C_BM_SCRIPT p4src/source_routing.p4 --json source_routing.json
+sudo PYTHONPATH=$PYTHONPATH:$BMV2_PATH/mininet/ python topo.py \
+    --behavioral-exe $BMV2_PATH/targets/simple_switch/simple_switch \
+    --json source_routing.json \
+    --cli $CLI_PATH
diff --git a/SIGCOMM_2015/source_routing/send.py b/SIGCOMM_2015/source_routing/send.py
new file mode 100755
index 0000000..e1a2503
--- /dev/null
+++ b/SIGCOMM_2015/source_routing/send.py
@@ -0,0 +1,106 @@
+#!/usr/bin/python
+
+# Copyright 2013-present Barefoot Networks, Inc. 
+# 
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+# 
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from scapy.all import sniff, sendp
+from scapy.all import Packet
+from scapy.all import ShortField, IntField, LongField, BitField
+
+import networkx as nx
+
+import sys
+
+class SrcRoute(Packet):
+    name = "SrcRoute"
+    fields_desc = [
+        LongField("preamble", 0),
+        IntField("num_valid", 0)
+    ]
+
+def read_topo():
+    nb_hosts = 0
+    nb_switches = 0
+    links = []
+    with open("topo.txt", "r") as f:
+        line = f.readline()[:-1]
+        w, nb_switches = line.split()
+        assert(w == "switches")
+        line = f.readline()[:-1]
+        w, nb_hosts = line.split()
+        assert(w == "hosts")
+        for line in f:
+            if not f: break
+            a, b = line.split()
+            links.append( (a, b) )
+    return int(nb_hosts), int(nb_switches), links
+
+def main():
+    if len(sys.argv) != 3:
+        print "Usage: send.py [this_host] [target_host]"
+        print "For example: send.py h1 h2"
+        sys.exit(1)
+
+    src, dst = sys.argv[1:]
+
+    nb_hosts, nb_switches, links = read_topo()
+
+    port_map = {}
+
+    for a, b in links:
+        if a not in port_map:
+            port_map[a] = {}
+        if b not in port_map:
+            port_map[b] = {}
+
+        assert(b not in port_map[a])
+        assert(a not in port_map[b])
+        port_map[a][b] = len(port_map[a]) + 1
+        port_map[b][a] = len(port_map[b]) + 1
+
+
+    G = nx.Graph()
+    for a, b in links:
+        G.add_edge(a, b)
+
+    shortest_paths = nx.shortest_path(G)
+    shortest_path = shortest_paths[src][dst]
+
+    print "path is:", shortest_path
+
+    port_list = []
+    first = shortest_path[1]
+    for h in shortest_path[2:]:
+        port_list.append(port_map[first][h])
+        first = h
+
+    print "port list is:", port_list
+
+    port_str = ""
+    for p in port_list:
+        port_str += chr(p)
+
+    while(1):
+        msg = raw_input("What do you want to send: ")
+
+        # finding the route
+        first = None
+
+        p = SrcRoute(num_valid = len(port_list)) / port_str / msg
+        print p.show()
+        sendp(p, iface = "eth0")
+        # print msg
+
+if __name__ == '__main__':
+    main()
diff --git a/SIGCOMM_2015/source_routing/solution.tar.gz b/SIGCOMM_2015/source_routing/solution.tar.gz
new file mode 100644
index 0000000..dd775a1
Binary files /dev/null and b/SIGCOMM_2015/source_routing/solution.tar.gz differ
diff --git a/SIGCOMM_2015/source_routing/topo.py b/SIGCOMM_2015/source_routing/topo.py
new file mode 100644
index 0000000..abfa57c
--- /dev/null
+++ b/SIGCOMM_2015/source_routing/topo.py
@@ -0,0 +1,129 @@
+#!/usr/bin/python
+
+# Copyright 2013-present Barefoot Networks, Inc. 
+# 
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+# 
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from mininet.net import Mininet
+from mininet.topo import Topo
+from mininet.log import setLogLevel, info
+from mininet.cli import CLI
+from mininet.link import TCLink
+
+from p4_mininet import P4Switch, P4Host
+
+import argparse
+from time import sleep
+import os
+import subprocess
+
+_THIS_DIR = os.path.dirname(os.path.realpath(__file__))
+_THRIFT_BASE_PORT = 22222
+
+parser = argparse.ArgumentParser(description='Mininet demo')
+parser.add_argument('--behavioral-exe', help='Path to behavioral executable',
+                    type=str, action="store", required=True)
+parser.add_argument('--json', help='Path to JSON config file',
+                    type=str, action="store", required=True)
+parser.add_argument('--cli', help='Path to BM CLI',
+                    type=str, action="store", required=True)
+
+args = parser.parse_args()
+
+class MyTopo(Topo):
+    def __init__(self, sw_path, json_path, nb_hosts, nb_switches, links, **opts):
+        # Initialize topology and default options
+        Topo.__init__(self, **opts)
+
+        for i in xrange(nb_switches):
+            switch = self.addSwitch('s%d' % (i + 1),
+                                    sw_path = sw_path,
+                                    json_path = json_path,
+                                    thrift_port = _THRIFT_BASE_PORT + i,
+                                    pcap_dump = True,
+                                    device_id = i)
+        
+        for h in xrange(nb_hosts):
+            host = self.addHost('h%d' % (h + 1))
+
+        for a, b in links:
+            self.addLink(a, b)
+
+def read_topo():
+    nb_hosts = 0
+    nb_switches = 0
+    links = []
+    with open("topo.txt", "r") as f:
+        line = f.readline()[:-1]
+        w, nb_switches = line.split()
+        assert(w == "switches")
+        line = f.readline()[:-1]
+        w, nb_hosts = line.split()
+        assert(w == "hosts")
+        for line in f:
+            if not f: break
+            a, b = line.split()
+            links.append( (a, b) )
+    return int(nb_hosts), int(nb_switches), links
+            
+
+def main():
+    nb_hosts, nb_switches, links = read_topo()
+
+    topo = MyTopo(args.behavioral_exe,
+                  args.json,
+                  nb_hosts, nb_switches, links)
+
+    net = Mininet(topo = topo,
+                  host = P4Host,
+                  switch = P4Switch,
+                  controller = None )
+    net.start()
+
+    for n in xrange(nb_hosts):
+        h = net.get('h%d' % (n + 1))
+        for off in ["rx", "tx", "sg"]:
+            cmd = "/sbin/ethtool --offload eth0 %s off" % off
+            print cmd
+            h.cmd(cmd)
+        print "disable ipv6"
+        h.cmd("sysctl -w net.ipv6.conf.all.disable_ipv6=1")
+        h.cmd("sysctl -w net.ipv6.conf.default.disable_ipv6=1")
+        h.cmd("sysctl -w net.ipv6.conf.lo.disable_ipv6=1")
+        h.cmd("sysctl -w net.ipv4.tcp_congestion_control=reno")
+        h.cmd("iptables -I OUTPUT -p icmp --icmp-type destination-unreachable -j DROP")
+
+    sleep(1)
+
+    for i in xrange(nb_switches):
+        cmd = [args.cli, "--json", args.json,
+               "--thrift-port", str(_THRIFT_BASE_PORT + i)]
+        with open("commands.txt", "r") as f:
+            print " ".join(cmd)
+            try:
+                output = subprocess.check_output(cmd, stdin = f)
+                print output
+            except subprocess.CalledProcessError as e:
+                print e
+                print e.output
+
+    sleep(1)
+
+    print "Ready !"
+
+    CLI( net )
+    net.stop()
+
+if __name__ == '__main__':
+    setLogLevel( 'info' )
+    main()
diff --git a/SIGCOMM_2015/source_routing/topo.txt b/SIGCOMM_2015/source_routing/topo.txt
new file mode 100644
index 0000000..08f8387
--- /dev/null
+++ b/SIGCOMM_2015/source_routing/topo.txt
@@ -0,0 +1,8 @@
+switches 3
+hosts 3
+h1 s1
+h2 s2
+h3 s3
+s1 s2
+s1 s3
+s2 s3