@Override
  public void addedSwitch(IOFSwitch sw) {
    /**
     * Insert static flows on all ports of the switch to redirect DHCP client --> DHCP DHCPServer
     * traffic to the controller. DHCP client's operate on UDP port 67
     */
    OFFlowMod flow = new OFFlowMod();
    OFMatch match = new OFMatch();
    ArrayList<OFAction> actionList = new ArrayList<OFAction>();
    OFActionOutput action = new OFActionOutput();
    String flowName;

    if (sw.getStringId().equals(ROOT_NODE_WIFI_OVS_DPID)) {
      // root node, WiFi bridge, patch to tunnel port
      flow = new OFFlowMod();
      match = new OFMatch();
      match.setInputPort(ROOT_NODE_WIFI_OVS_PATCH);
      action.setType(OFActionType.OUTPUT);
      action.setPort(ROOT_NODE_WIFI_OVS_TUNNEL);
      action.setLength((short) OFActionOutput.MINIMUM_LENGTH);
      actionList.add(action);
      flow.setCookie(0);
      flow.setBufferId(-1);
      flow.setOutPort(ROOT_NODE_WIFI_OVS_TUNNEL);
      flow.setActions(actionList);
      flow.setMatch(match);
      flow.setPriority(PRIORITY_HIGH);
      flow.setLengthU(OFFlowMod.MINIMUM_LENGTH + action.getLengthU());
      flowName = "root-node-wifi-br-patch-tun";
      sfp.addFlow(flowName, flow, sw.getStringId());
      log.info("added flow on SW " + sw.getStringId() + flowName);
      actionList.clear();
      // root node, WiFi bridge, physical to patch
      flow = new OFFlowMod();
      match = new OFMatch();
      match.setInputPort(ROOT_NODE_WIFI_OVS_TUNNEL);
      action.setType(OFActionType.OUTPUT);
      action.setPort(ROOT_NODE_WIFI_OVS_PATCH);
      action.setLength((short) OFActionOutput.MINIMUM_LENGTH);
      actionList.add(action);
      flow.setCookie(0);
      flow.setBufferId(-1);
      flow.setOutPort(ROOT_NODE_WIFI_OVS_PATCH);
      flow.setActions(actionList);
      flow.setMatch(match);
      flow.setPriority(PRIORITY_HIGH);
      flow.setLengthU(OFFlowMod.MINIMUM_LENGTH + action.getLengthU());
      flowName = "root-node-wifi-br-tun-patch";
      sfp.addFlow(flowName, flow, sw.getStringId());
      log.info("added flow on SW " + sw.getStringId() + flowName);
      actionList.clear();
    } else if (sw.getStringId().equals(ROOT_NODE_WIMAX_OVS_DPID)) {
      // root node, WiMAX bridge, patch to physical
      flow = new OFFlowMod();
      match = new OFMatch();
      match.setInputPort(ROOT_NODE_WIMAX_OVS_PATCH);
      action.setType(OFActionType.OUTPUT);
      action.setPort(ROOT_NODE_WIMAX_OVS_VLAN);
      action.setLength((short) OFActionOutput.MINIMUM_LENGTH);
      actionList.add(action);
      flow.setCookie(0);
      flow.setBufferId(-1);
      flow.setOutPort(ROOT_NODE_WIMAX_OVS_VLAN);
      flow.setActions(actionList);
      flow.setMatch(match);
      flow.setPriority(PRIORITY_HIGH);
      flow.setLengthU(OFFlowMod.MINIMUM_LENGTH + action.getLengthU());
      flowName = "root-node-wimax-br-patch-phys";
      sfp.addFlow(flowName, flow, sw.getStringId());
      log.info("added flow on SW " + sw.getStringId() + flowName);
      actionList.clear();
      // root node, WiMAX bridge, interface to patch
      flow = new OFFlowMod();
      match = new OFMatch();
      match.setInputPort(ROOT_NODE_WIMAX_OVS_VLAN);
      action.setType(OFActionType.OUTPUT);
      action.setPort(ROOT_NODE_WIMAX_OVS_PATCH);
      action.setLength((short) OFActionOutput.MINIMUM_LENGTH);
      actionList.add(action);
      flow.setCookie(0);
      flow.setBufferId(-1);
      flow.setOutPort(ROOT_NODE_WIMAX_OVS_PATCH);
      flow.setActions(actionList);
      flow.setMatch(match);
      flow.setPriority(PRIORITY_HIGH);
      flow.setLengthU(OFFlowMod.MINIMUM_LENGTH + action.getLengthU());
      flowName = "root-node-wimax-br-phys-patch";
      sfp.addFlow(flowName, flow, sw.getStringId());
      log.info("added flow on SW " + sw.getStringId() + flowName);
      actionList.clear();
      // root node, WiMAX bridge, DHCP on physical
      match.setInputPort(ROOT_NODE_WIMAX_OVS_VLAN);
      match.setDataLayerType(Ethernet.TYPE_IPv4);
      match.setNetworkProtocol(IPv4.PROTOCOL_UDP);
      match.setTransportSource(UDP.DHCP_CLIENT_PORT);
      action.setType(OFActionType.OUTPUT);
      action.setLength((short) OFActionOutput.MINIMUM_LENGTH);
      action.setPort(OFPort.OFPP_CONTROLLER.getValue());
      actionList.add(action);
      flow.setCookie(0);
      flow.setBufferId(-1);
      flow.setOutPort(OFPort.OFPP_CONTROLLER.getValue());
      flow.setActions(actionList);
      flow.setMatch(match);
      flow.setPriority(PRIORITY_MAX);
      flow.setLengthU(OFFlowMod.MINIMUM_LENGTH + action.getLengthU());
      flowName = "root-node-wimax-br-DHCP-phys";
      sfp.addFlow(flowName, flow, sw.getStringId());
      log.info("added flow on SW " + sw.getStringId() + flowName);
      actionList.clear();
    } else if (sw.getStringId().equals(ROOT_NODE_ROOT_OVS_DPID)) {
      // root node, root bridge, patch AP3 (WiFi) to Linux
      flow = new OFFlowMod();
      match = new OFMatch();
      match.setInputPort(ROOT_NODE_ROOT_OVS_WIFI_PATCH);
      action.setType(OFActionType.OUTPUT);
      action.setPort(OFPort.OFPP_LOCAL.getValue());
      action.setLength((short) OFActionOutput.MINIMUM_LENGTH);
      actionList.add(action);
      flow.setCookie(0);
      flow.setBufferId(-1);
      flow.setOutPort(OFPort.OFPP_LOCAL.getValue());
      flow.setActions(actionList);
      flow.setMatch(match);
      flow.setPriority(PRIORITY_HIGH);
      flow.setLengthU(OFFlowMod.MINIMUM_LENGTH + action.getLengthU());
      flowName = "root-node-root-br-patchWiFi-linux";
      sfp.addFlow(flowName, flow, sw.getStringId());
      log.info("added flow on SW " + sw.getStringId() + flowName);
      actionList.clear();
      // root node, root bridge, patch WiMAX to Linux
      flow = new OFFlowMod();
      match = new OFMatch();
      match.setInputPort(ROOT_NODE_ROOT_OVS_WIMAX_PATCH);
      action.setType(OFActionType.OUTPUT);
      action.setPort(OFPort.OFPP_LOCAL.getValue());
      action.setLength((short) OFActionOutput.MINIMUM_LENGTH);
      actionList.add(action);
      flow.setCookie(0);
      flow.setBufferId(-1);
      flow.setOutPort(OFPort.OFPP_LOCAL.getValue());
      flow.setActions(actionList);
      flow.setMatch(match);
      flow.setPriority(PRIORITY_HIGH);
      flow.setLengthU(OFFlowMod.MINIMUM_LENGTH + action.getLengthU());
      flowName = "root-node-root-br-patchWiMAX-linux";
      sfp.addFlow(flowName, flow, sw.getStringId());
      log.info("added flow on SW " + sw.getStringId() + flowName);
      actionList.clear();
      // root node, root bridge, physical to Linux
      // flow = new OFFlowMod();
      // match = new OFMatch();
      // match.setInputPort((short) 1);
      // action.setType(OFActionType.OUTPUT);
      // action.setPort(OFPort.OFPP_LOCAL.getValue());
      // action.setLength((short) OFActionOutput.MINIMUM_LENGTH);
      // actionList.add(action);
      // flow.setCookie(0);
      // flow.setBufferId(-1);
      // flow.setOutPort(OFPort.OFPP_LOCAL.getValue());
      // flow.setActions(actionList);
      // flow.setMatch(match);
      // flow.setPriority(PRIORITY_HIGH);
      // flow.setLengthU(OFFlowMod.MINIMUM_LENGTH + action.getLengthU());
      // flowName = "root-ovs-root-br-phys-linux";
      // sfp.addFlow(flowName, flow, sw.getStringId());
      // log.info("added flow on SW " + sw.getStringId() + flowName);
      // actionList.clear();
      // root node, root bridge, Linux to physical (match extra: src-ip of root node...i.e. it's
      // outbound)
      // flow = new OFFlowMod();
      // match = new OFMatch();
      // match.setInputPort(OFPort.OFPP_LOCAL.getValue());
      // match.setDataLayerType(Ethernet.TYPE_IPv4); // ... IP packets ... required for a match on
      // an IP address
      // match.setNetworkSource(ROOT_NODE_ROOT_OVS_IP);
      // action.setType(OFActionType.OUTPUT);
      // action.setPort((short) 1);
      // action.setLength((short) OFActionOutput.MINIMUM_LENGTH);
      // actionList.add(action);
      // flow.setCookie(0);
      // flow.setBufferId(-1);
      // flow.setOutPort((short) 1);
      // flow.setActions(actionList);
      // flow.setMatch(match);
      // flow.setPriority(PRIORITY_HIGH);
      // flow.setLengthU(OFFlowMod.MINIMUM_LENGTH + action.getLengthU());
      // flowName = "root-ovs-root-br-linux-phys-egress";
      // sfp.addFlow(flowName, flow, sw.getStringId());
      // log.info("added flow on SW " + sw.getStringId() + flowName);
      // actionList.clear();
    } else if (sw.getStringId().equals(WIFI_NODE_WIFI_OVS_DPID)) {
      // WiFi node, WiFi bridge, physical to patch
      flow = new OFFlowMod();
      match = new OFMatch();
      match.setInputPort((short) 1);
      action.setType(OFActionType.OUTPUT);
      action.setPort(WIFI_NODE_WIFI_OVS_PATCH);
      action.setLength((short) OFActionOutput.MINIMUM_LENGTH);
      actionList.add(action);
      flow.setCookie(0);
      flow.setBufferId(-1);
      flow.setOutPort(WIFI_NODE_WIFI_OVS_PATCH);
      flow.setActions(actionList);
      flow.setMatch(match);
      flow.setPriority(PRIORITY_HIGH);
      flow.setLengthU(OFFlowMod.MINIMUM_LENGTH + action.getLengthU());
      flowName = "wifi-node-wifi-br-phys-patch";
      sfp.addFlow(flowName, flow, sw.getStringId());
      log.info("added flow on SW " + sw.getStringId() + flowName);
      actionList.clear();
      // WiFi node, WiFi bridge, patch to physical
      flow = new OFFlowMod();
      match = new OFMatch();
      match.setInputPort(WIFI_NODE_WIFI_OVS_PATCH);
      action.setType(OFActionType.OUTPUT);
      action.setPort((short) 1);
      action.setLength((short) OFActionOutput.MINIMUM_LENGTH);
      actionList.add(action);
      flow.setCookie(0);
      flow.setBufferId(-1);
      flow.setOutPort((short) 1);
      flow.setActions(actionList);
      flow.setMatch(match);
      flow.setPriority(PRIORITY_HIGH);
      flow.setLengthU(OFFlowMod.MINIMUM_LENGTH + action.getLengthU());
      flowName = "wifi-node-wifi-br-patch-phys";
      sfp.addFlow(flowName, flow, sw.getStringId());
      log.info("added flow on SW " + sw.getStringId() + flowName);
      actionList.clear();
      // root node, WiMAX bridge, DHCP on physical
      match.setInputPort((short) 1);
      match.setDataLayerType(Ethernet.TYPE_IPv4);
      match.setNetworkProtocol(IPv4.PROTOCOL_UDP);
      match.setTransportSource(UDP.DHCP_CLIENT_PORT);
      action.setType(OFActionType.OUTPUT);
      action.setLength((short) OFActionOutput.MINIMUM_LENGTH);
      action.setPort(OFPort.OFPP_CONTROLLER.getValue());
      actionList.add(action);
      flow.setCookie(0);
      flow.setBufferId(-1);
      flow.setOutPort(OFPort.OFPP_CONTROLLER.getValue());
      flow.setActions(actionList);
      flow.setMatch(match);
      flow.setPriority(PRIORITY_MAX);
      flow.setLengthU(OFFlowMod.MINIMUM_LENGTH + action.getLengthU());
      flowName = "wifi-node-wifi-br-DHCP-phys";
      sfp.addFlow(flowName, flow, sw.getStringId());
      log.info("added flow on SW " + sw.getStringId() + flowName);
      actionList.clear();
    } else if (sw.getStringId().equals(WIFI_NODE_TUNNEL_OVS_DPID)) {
      // WiFi node, tunnel bridge, tunnel to patch
      flow = new OFFlowMod();
      match = new OFMatch();
      match.setInputPort(WIFI_NODE_TUNNEL_OVS_TUNNEL);
      action.setType(OFActionType.OUTPUT);
      action.setPort(WIFI_NODE_TUNNEL_OVS_PATCH);
      action.setLength((short) OFActionOutput.MINIMUM_LENGTH);
      actionList.add(action);
      flow.setCookie(0);
      flow.setBufferId(-1);
      flow.setOutPort(WIFI_NODE_TUNNEL_OVS_PATCH);
      flow.setActions(actionList);
      flow.setMatch(match);
      flow.setPriority(PRIORITY_HIGH);
      flow.setLengthU(OFFlowMod.MINIMUM_LENGTH + action.getLengthU());
      flowName = "wifi-node-tunnel-br-tun-patch";
      sfp.addFlow(flowName, flow, sw.getStringId());
      log.info("added flow on SW " + sw.getStringId() + flowName);
      actionList.clear();
      // WiFi node, tunnel bridge, patch to tunnel
      flow = new OFFlowMod();
      match = new OFMatch();
      match.setInputPort(WIFI_NODE_TUNNEL_OVS_PATCH);
      action.setType(OFActionType.OUTPUT);
      action.setPort(WIFI_NODE_TUNNEL_OVS_TUNNEL);
      action.setLength((short) OFActionOutput.MINIMUM_LENGTH);
      actionList.add(action);
      flow.setCookie(0);
      flow.setBufferId(-1);
      flow.setOutPort(WIFI_NODE_TUNNEL_OVS_TUNNEL);
      flow.setActions(actionList);
      flow.setMatch(match);
      flow.setPriority(PRIORITY_HIGH);
      flow.setLengthU(OFFlowMod.MINIMUM_LENGTH + action.getLengthU());
      flowName = "wifi-node-tunnel-br-patch-tun";
      sfp.addFlow(flowName, flow, sw.getStringId());
      log.info("added flow on SW " + sw.getStringId() + flowName);
      actionList.clear();
    }
  }