diff --git a/examples/csma-bridge.py b/examples/csma-bridge.py
new file mode 100644
index 000000000..b5778fea0
--- /dev/null
+++ b/examples/csma-bridge.py
@@ -0,0 +1,155 @@
+# /*
+#  * This program is free software; you can redistribute it and/or modify
+#  * it under the terms of the GNU General Public License version 2 as
+#  * published by the Free Software Foundation
+#  *
+#  * This program is distributed in the hope that it will be useful,
+#  * but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  * GNU General Public License for more details.
+#  *
+#  * You should have received a copy of the GNU General Public License
+#  * along with this program; if not, write to the Free Software
+#  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+#  */
+
+# Network topology
+#
+#        n0     n1  
+#        |      | 
+#       ----------
+#       | Switch |
+#       ----------
+#        |      | 
+#        n2     n3  
+#
+#
+# - CBR/UDP flows from n0 to n1 and from n3 to n0
+# - DropTail queues 
+# - Tracing of queues and packet receptions to file "csma-bridge.tr"
+
+import ns3
+
+
+def main(argv):
+    #
+    # Make the random number generators generate reproducible results.
+    #
+    ns3.RandomVariable.UseGlobalSeed(1, 1, 2, 3, 5, 8)
+
+    #
+    # Allow the user to override any of the defaults and the above Bind() at
+    # run-time, via command-line arguments
+    #
+    cmd = ns3.CommandLine()
+    cmd.Parse(argv)
+
+    #
+    # Explicitly create the nodes required by the topology(shown above).
+    #
+    print "Create nodes."
+    terminals = ns3.NodeContainer()
+    terminals.Create(4)
+
+    csmaSwitch = ns3.NodeContainer()
+    csmaSwitch.Create(1)
+
+    print "Build Topology"
+    csma = ns3.CsmaHelper()
+    csma.SetChannelAttribute("DataRate", ns3.DataRateValue(ns3.DataRate(5000000)))
+    csma.SetChannelAttribute("Delay", ns3.TimeValue(ns3.MilliSeconds(2)))
+
+    # Create the csma links, from each terminal to the switch
+
+    terminalDevices = ns3.NetDeviceContainer()
+    switchDevices = ns3.NetDeviceContainer()
+
+    for i in range(4):
+        link = csma.Install(ns3.NodeContainer(ns3.NodeContainer(terminals.Get(i)), csmaSwitch))
+        terminalDevices.Add(link.Get(0))
+        switchDevices.Add(link.Get(1))
+
+    # Create the bridge netdevice, which will do the packet switching
+    switchNode = csmaSwitch.Get(0)
+    bridgeDevice = ns3.BridgeNetDevice()
+    switchNode.AddDevice(bridgeDevice)
+
+    for portIter in range(switchDevices.GetN()):
+        bridgeDevice.AddBridgePort(switchDevices.Get(portIter))
+
+    # Add internet stack to the terminals
+    internet = ns3.InternetStackHelper()
+    internet.Install(terminals)
+
+    # We've got the "hardware" in place.  Now we need to add IP addresses.
+    #
+    print "Assign IP Addresses."
+    ipv4 = ns3.Ipv4AddressHelper()
+    ipv4.SetBase(ns3.Ipv4Address("10.1.1.0"), ns3.Ipv4Mask("255.255.255.0"))
+    ipv4.Assign(terminalDevices)
+
+    #
+    # Create an OnOff application to send UDP datagrams from node zero to node 1.
+    #
+    print "Create Applications."
+    port = 9   # Discard port(RFC 863)
+
+    onoff = ns3.OnOffHelper("ns3::UdpSocketFactory", 
+                            ns3.Address(ns3.InetSocketAddress(ns3.Ipv4Address("10.1.1.2"), port)))
+    onoff.SetAttribute("OnTime", ns3.RandomVariableValue(ns3.ConstantVariable(1)))
+    onoff.SetAttribute("OffTime", ns3.RandomVariableValue(ns3.ConstantVariable(0)))
+
+    app = onoff.Install(ns3.NodeContainer(terminals.Get(0)))
+    # Start the application
+    app.Start(ns3.Seconds(1.0))
+    app.Stop(ns3.Seconds(10.0))
+
+    # Create an optional packet sink to receive these packets
+    sink = ns3.PacketSinkHelper("ns3::UdpSocketFactory",
+                                ns3.Address(ns3.InetSocketAddress(ns3.Ipv4Address.GetAny(), port)))
+    sink.Install(ns3.NodeContainer(terminals.Get(1)))
+
+    # 
+    # Create a similar flow from n3 to n0, starting at time 1.1 seconds
+    #
+    onoff.SetAttribute("Remote", 
+                       ns3.AddressValue(ns3.InetSocketAddress(ns3.Ipv4Address("10.1.1.1"), port)))
+    app2 = onoff.Install(ns3.NodeContainer(terminals.Get(3)))
+
+    sink.Install(ns3.NodeContainer(terminals.Get(0)))
+
+    app2.Start(ns3.Seconds(1.1))
+    app2.Stop(ns3.Seconds(10.0))
+
+    #
+    # Configure tracing of all enqueue, dequeue, and NetDevice receive events.
+    # Trace output will be sent to the file "csma-bridge.tr"
+    #
+    #print "Configure Tracing."
+    #std.ofstream ascii
+    #ascii.open("csma-bridge.tr")
+    #CsmaHelper.EnableAsciiAll(ascii)
+
+    #
+    # Also configure some tcpdump traces; each interface will be traced.
+    # The output files will be named:
+    #     csma-bridge.pcap-<nodeId>-<interfaceId>
+    # and can be read by the "tcpdump -r" command(use "-tt" option to
+    # display timestamps correctly)
+    #
+    ns3.CsmaHelper.EnablePcapAll("csma-bridge")
+
+    #
+    # Now, do the actual simulation.
+    #
+    print "Run Simulation."
+    ns3.Simulator.Run()
+    ns3.Simulator.Destroy()
+    print "Done."
+
+
+
+if __name__ == '__main__':
+    import sys
+    main(sys.argv)
+