diff --git a/src/emuvim/api/rest/network.py b/src/emuvim/api/rest/network.py
index 83fbde7..63696a0 100755
--- a/src/emuvim/api/rest/network.py
+++ b/src/emuvim/api/rest/network.py
@@ -87,6 +87,10 @@
             bidirectional = data.get("bidirectional")
             cookie = data.get("cookie")
             priority = data.get("priority")
+            skip_vlan_tag = data.get("skip_vlan_tag")
+            monitor = data.get("monitor")
+            monitor_placement = data.get("monitor_placement")
+
             c = net.setChain(
                 vnf_src_name, vnf_dst_name,
                 vnf_src_interface=vnf_src_interface,
@@ -96,7 +100,10 @@
                 match=match,
                 bidirectional=bidirectional,
                 cookie=cookie,
-                priority=priority)
+                priority=priority,
+                skip_vlan_tag=skip_vlan_tag,
+                monitor=monitor,
+                monitor_placement=monitor_placement)
             # return setChain response
             return str(c), 200
         except Exception as ex:
diff --git a/src/emuvim/api/sonata/dummygatekeeper.py b/src/emuvim/api/sonata/dummygatekeeper.py
index 70fce59..5936d94 100755
--- a/src/emuvim/api/sonata/dummygatekeeper.py
+++ b/src/emuvim/api/sonata/dummygatekeeper.py
@@ -75,6 +75,7 @@
     def __init__(self):
         self.services = dict()
         self.dcs = dict()
+        self.net = None
         self.vnf_counter = 0  # used to generate short names for VNFs (Mininet limitation)
         LOG.info("Create SONATA dummy gatekeeper.")
 
@@ -180,6 +181,9 @@
         eline_fwd_links = [l for l in vlinks if (l["id"] in fwd_links) and (l["connectivity_type"] == "E-Line")]
         elan_fwd_links = [l for l in vlinks if (l["id"] in fwd_links) and (l["connectivity_type"] == "E-LAN")]
 
+        GK.net.deployed_elines.extend(eline_fwd_links)
+        GK.net.deployed_elans.extend(elan_fwd_links)
+
         # 4a. deploy E-Line links
         # cookie is used as identifier for the flowrules installed by the dummygatekeeper
         # eg. different services get a unique cookie for their flowrules
@@ -227,6 +231,9 @@
         # 4b. deploy E-LAN links
         base = 10
         for link in elan_fwd_links:
+
+            elan_vnf_list=[]
+
             # generate lan ip address
             ip = 1
             for intf in link["connection_points_reference"]:
@@ -235,6 +242,8 @@
                 if vnf_id in self.sap_identifiers:
                     src_docker_name = "{0}_{1}".format(vnf_id, intf_name)
                     vnf_id = src_docker_name
+                else:
+                    src_docker_name = vnf_id
                 vnf_name = vnf_id2vnf_name[vnf_id]
                 LOG.debug(
                     "Setting up E-LAN link. %s(%s:%s) -> %s" % (
@@ -249,6 +258,14 @@
                         self._vnf_reconfigure_network(vnfi, intf_name, ip_address)
                         # increase for the next ip address on this E-LAN
                         ip += 1
+
+                        # add this vnf and interface to the E-LAN for tagging
+                        network = self.vnfds[vnf_name].get("dc").net  # there should be a cleaner way to find the DCNetwork
+                        elan_vnf_list.append({'name':src_docker_name,'interface':intf_name})
+
+
+            # install the VLAN tags for this E-LAN
+            network.setLAN(elan_vnf_list)
             # increase the base ip address for the next E-LAN
             base += 1
 
@@ -408,6 +425,7 @@
                 self.package_content_path,
                 make_relative_path(self.manifest.get("entry_service_template")))
             self.nsd = load_yaml(nsd_path)
+            GK.net.deployed_nsds.append(self.nsd)
             LOG.debug("Loaded NSD: %r" % self.nsd.get("name"))
 
     def _load_vnfd(self):
@@ -697,6 +715,7 @@
 
 def start_rest_api(host, port, datacenters=dict()):
     GK.dcs = datacenters
+    GK.net = get_dc_network()
     # start the Flask server (not the best performance but ok for our use case)
     app.run(host=host,
             port=port,
@@ -745,6 +764,14 @@
         r.append("%d.0.0.%d/%d" % (i, ip, subnet_size))
     return r
 
+def get_dc_network():
+    """
+    retrieve the DCnetwork where this dummygatekeeper (GK) connects to.
+    Assume at least 1 datacenter is connected to this GK, and that all datacenters belong to the same DCNetwork
+    :return:
+    """
+    assert (len(GK.dcs) > 0)
+    return GK.dcs.values()[0].net
 
 if __name__ == '__main__':
     """
diff --git a/src/emuvim/api/sonata/sap_vnfd.yml b/src/emuvim/api/sonata/sap_vnfd.yml
old mode 100644
new mode 100755
diff --git a/src/emuvim/cli/rest/compute.py b/src/emuvim/cli/rest/compute.py
index b92fd4f..9e5e0ab 100755
--- a/src/emuvim/cli/rest/compute.py
+++ b/src/emuvim/cli/rest/compute.py
@@ -30,6 +30,7 @@
 import pprint
 import argparse
 import json
+from subprocess import Popen
 
 pp = pprint.PrettyPrinter(indent=4)
 
@@ -77,18 +78,21 @@
             if len(c) > 1:
                 name = c[0]
                 status = c[1]
-                eth0ip = status.get("docker_network", "-")
+                #eth0ip = status.get("docker_network", "-")
+                netw_list = [netw_dict['intf_name'] for netw_dict in status.get("network")]
+                dc_if_list = [netw_dict['dc_portname'] for netw_dict in status.get("network")]
                 table.append([status.get("datacenter"),
                               name,
                               status.get("image"),
-                              eth0ip,
-                              status.get("state").get("Status")])
+                              ','.join(netw_list),
+                              ','.join(dc_if_list)])
+                #status.get("state").get("Status")]
 
         headers = ["Datacenter",
                    "Container",
                    "Image",
-                   "docker0",
-                   "Status"]
+                   "Interface list",
+                   "Datacenter interfaces"]
         print(tabulate(table, headers=headers, tablefmt="grid"))
 
     def status(self, args):
@@ -100,6 +104,11 @@
 
         pp.pprint(list)
 
+    def xterm(self, args):
+        vnf_names = args.get("vnf_names")
+        for vnf_name in vnf_names:
+            Popen(['xterm', '-xrm', 'XTerm.vt100.allowTitleOps: false', '-T', vnf_name,
+                   '-e', "docker exec -it mn.{0} /bin/bash".format(vnf_name)])
 
 parser = argparse.ArgumentParser(description="""son-emu compute
     
@@ -110,9 +119,13 @@
     """, formatter_class=argparse.RawTextHelpFormatter)
 parser.add_argument(
     "command",
-    choices=['start', 'stop', 'list', 'status'],
+    choices=['start', 'stop', 'list', 'status', 'xterm'],
     help="Action to be executed.")
 parser.add_argument(
+    "vnf_names",
+    nargs='*',
+    help="vnf names to open an xterm for")
+parser.add_argument(
     "--datacenter", "-d", dest="datacenter",
     help="Data center to which the command should be applied.")
 parser.add_argument(
diff --git a/src/emuvim/dcemulator/net.py b/src/emuvim/dcemulator/net.py
index 15bb6f1..731331b 100755
--- a/src/emuvim/dcemulator/net.py
+++ b/src/emuvim/dcemulator/net.py
@@ -32,6 +32,7 @@
 from subprocess import Popen
 import re
 import requests
+import os
 
 from mininet.net import Containernet
 from mininet.node import Controller, DefaultController, OVSSwitch, OVSKernelSwitch, Docker, RemoteController
@@ -55,7 +56,7 @@
     """
 
     def __init__(self, controller=RemoteController, monitor=False,
-                 enable_learning = True,   # in case of RemoteController (Ryu), learning switch behavior can be turned off/on
+                 enable_learning=False, # learning switch behavior of the default ovs switches icw Ryu controller can be turned off/on, neede for E-LAN functionality
                  dc_emulation_max_cpu=1.0,  # fraction of overall CPU time for emulation
                  dc_emulation_max_mem=512,  # emulation max mem in MB
                  **kwargs):
@@ -68,6 +69,12 @@
         # members
         self.dcs = {}
         self.ryu_process = None
+        #list of deployed nsds.E_Lines and E_LANs (uploaded from the dummy gatekeeper)
+        self.deployed_nsds = []
+        self.deployed_elines = []
+        self.deployed_elans = []
+        self.installed_chains = []
+
 
         # always cleanup environment before we start the emulator
         self.killRyu()
@@ -77,10 +84,18 @@
         Containernet.__init__(
             self, switch=OVSKernelSwitch, controller=controller, **kwargs)
 
+        # default switch configuration
+        enable_ryu_learning = False
+        if enable_learning :
+            self.failMode = 'standalone'
+            enable_ryu_learning = True
+        else:
+            self.failMode = 'secure'
+
         # Ryu management
         if controller == RemoteController:
             # start Ryu controller
-            self.startRyu(learning_switch=enable_learning)
+            self.startRyu(learning_switch=enable_ryu_learning)
 
         # add the specified controller
         self.addController('c0', controller=controller)
@@ -127,7 +142,7 @@
         """
         assert node1 is not None
         assert node2 is not None
-        LOG.debug("addLink: n1=%s n2=%s" % (str(node1), str(node2)))
+
         # ensure type of node1
         if isinstance( node1, basestring ):
             if node1 in self.dcs:
@@ -205,6 +220,9 @@
         attr_dict2.update(attr_dict)
         self.DCNetwork_graph.add_edge(node2.name, node1.name, attr_dict=attr_dict2)
 
+        LOG.debug("addLink: n1={0} intf1={1} -- n2={2} intf2={3}".format(
+            str(node1),node1_port_name, str(node2), node2_port_name))
+
         return link
 
     def addDocker( self, label, **params ):
@@ -225,9 +243,26 @@
         """
         Wrapper for addSwitch method to store switch also in graph.
         """
+
+        # add this switch to the global topology overview
         if add_to_graph:
             self.DCNetwork_graph.add_node(name)
-        return Containernet.addSwitch(self, name, protocols='OpenFlow10,OpenFlow12,OpenFlow13', **params)
+
+        # set the learning switch behavior
+        if 'failMode' in params :
+            failMode = params['failMode']
+        else :
+            failMode = self.failMode
+
+        s = Containernet.addSwitch(self, name, protocols='OpenFlow10,OpenFlow12,OpenFlow13', failMode=failMode, **params)
+
+        # set flow entry that enables learning switch behavior (needed to enable E-LAN functionality)
+        #LOG.info('failmode {0}'.format(failMode))
+        #if failMode == 'standalone' :
+        #    LOG.info('add NORMAL')
+        #    s.dpctl('add-flow', 'actions=NORMAL')
+
+        return s
 
     def getAllContainers(self):
         """
@@ -260,6 +295,182 @@
     def CLI(self):
         CLI(self)
 
+    def setLAN(self, vnf_list):
+        """
+        setup an E-LAN network by assigning the same VLAN tag to each DC interface of the VNFs in the E-LAN
+
+        :param vnf_list: names of the VNFs in this E-LAN  [{name:,interface:},...]
+        :return:
+        """
+        src_sw = None
+        src_sw_inport_nr = 0
+        src_sw_inport_name = None
+
+        # get a vlan tag for this E-LAN
+        vlan = self.vlans.pop()
+
+        for vnf in vnf_list:
+            vnf_src_name = vnf['name']
+            vnf_src_interface = vnf['interface']
+
+            # check if port is specified (vnf:port)
+            if vnf_src_interface is None:
+                # take first interface by default
+                connected_sw = self.DCNetwork_graph.neighbors(vnf_src_name)[0]
+                link_dict = self.DCNetwork_graph[vnf_src_name][connected_sw]
+                vnf_src_interface = link_dict[0]['src_port_id']
+
+            for connected_sw in self.DCNetwork_graph.neighbors(vnf_src_name):
+                link_dict = self.DCNetwork_graph[vnf_src_name][connected_sw]
+                for link in link_dict:
+                    if (link_dict[link]['src_port_id'] == vnf_src_interface or
+                                link_dict[link]['src_port_name'] == vnf_src_interface):  # Fix: we might also get interface names, e.g, from a son-emu-cli call
+                        # found the right link and connected switch
+                        src_sw = connected_sw
+                        src_sw_inport_nr = link_dict[link]['dst_port_nr']
+                        src_sw_inport_name = link_dict[link]['dst_port_name']
+                        break
+
+            # set the tag on the dc switch interface
+            LOG.debug('set E-LAN: vnf name: {0} interface: {1} tag: {2}'.format(vnf_src_name, vnf_src_interface,vlan))
+            switch_node = self.getNodeByName(src_sw)
+            self._set_vlan_tag(switch_node, src_sw_inport_name, vlan)
+
+    def _addMonitorFlow(self, vnf_src_name, vnf_dst_name, vnf_src_interface=None, vnf_dst_interface=None,
+                       tag=None, **kwargs):
+
+        src_sw = None
+        src_sw_inport_nr = 0
+        src_sw_inport_name = None
+        dst_sw = None
+        dst_sw_outport_nr = 0
+        dst_sw_outport_name = None
+
+        LOG.debug("call AddMonitorFlow vnf_src_name=%r, vnf_src_interface=%r, vnf_dst_name=%r, vnf_dst_interface=%r",
+                  vnf_src_name, vnf_src_interface, vnf_dst_name, vnf_dst_interface)
+
+        #check if port is specified (vnf:port)
+        if vnf_src_interface is None:
+            # take first interface by default
+            connected_sw = self.DCNetwork_graph.neighbors(vnf_src_name)[0]
+            link_dict = self.DCNetwork_graph[vnf_src_name][connected_sw]
+            vnf_src_interface = link_dict[0]['src_port_id']
+
+        for connected_sw in self.DCNetwork_graph.neighbors(vnf_src_name):
+            link_dict = self.DCNetwork_graph[vnf_src_name][connected_sw]
+            for link in link_dict:
+                if (link_dict[link]['src_port_id'] == vnf_src_interface or
+                        link_dict[link]['src_port_name'] == vnf_src_interface):  # Fix: we might also get interface names, e.g, from a son-emu-cli call
+                    # found the right link and connected switch
+                    src_sw = connected_sw
+                    src_sw_inport_nr = link_dict[link]['dst_port_nr']
+                    src_sw_inport_name = link_dict[link]['dst_port_name']
+                    break
+
+        if vnf_dst_interface is None:
+            # take first interface by default
+            connected_sw = self.DCNetwork_graph.neighbors(vnf_dst_name)[0]
+            link_dict = self.DCNetwork_graph[connected_sw][vnf_dst_name]
+            vnf_dst_interface = link_dict[0]['dst_port_id']
+
+        vnf_dst_name = vnf_dst_name.split(':')[0]
+        for connected_sw in self.DCNetwork_graph.neighbors(vnf_dst_name):
+            link_dict = self.DCNetwork_graph[connected_sw][vnf_dst_name]
+            for link in link_dict:
+                if link_dict[link]['dst_port_id'] == vnf_dst_interface or \
+                        link_dict[link]['dst_port_name'] == vnf_dst_interface:  # Fix: we might also get interface names, e.g, from a son-emu-cli call
+                    # found the right link and connected switch
+                    dst_sw = connected_sw
+                    dst_sw_outport_nr = link_dict[link]['src_port_nr']
+                    dst_sw_outport_name = link_dict[link]['src_port_name']
+                    break
+
+        if not tag >= 0:
+            LOG.exception('tag not valid: {0}'.format(tag))
+
+        # get shortest path
+        try:
+            # returns the first found shortest path
+            # if all shortest paths are wanted, use: all_shortest_paths
+            path = nx.shortest_path(self.DCNetwork_graph, src_sw, dst_sw, weight=kwargs.get('weight'))
+        except:
+            LOG.exception("No path could be found between {0} and {1} using src_sw={2} and dst_sw={3}".format(
+                vnf_src_name, vnf_dst_name, src_sw, dst_sw))
+            LOG.debug("Graph nodes: %r" % self.DCNetwork_graph.nodes())
+            LOG.debug("Graph edges: %r" % self.DCNetwork_graph.edges())
+            for e, v in self.DCNetwork_graph.edges():
+                LOG.debug("%r" % self.DCNetwork_graph[e][v])
+            return "No path could be found between {0} and {1}".format(vnf_src_name, vnf_dst_name)
+
+        LOG.info("Path between {0} and {1}: {2}".format(vnf_src_name, vnf_dst_name, path))
+
+        current_hop = src_sw
+        switch_inport_nr = src_sw_inport_nr
+
+        cmd = kwargs.get('cmd')
+
+        #iterate through the path to install the flow-entries
+        for i in range(0,len(path)):
+            current_node = self.getNodeByName(current_hop)
+
+            if path.index(current_hop) < len(path)-1:
+                next_hop = path[path.index(current_hop)+1]
+            else:
+                #last switch reached
+                next_hop = vnf_dst_name
+
+            next_node = self.getNodeByName(next_hop)
+
+            if next_hop == vnf_dst_name:
+                switch_outport_nr = dst_sw_outport_nr
+                LOG.info("end node reached: {0}".format(vnf_dst_name))
+            elif not isinstance( next_node, OVSSwitch ):
+                LOG.info("Next node: {0} is not a switch".format(next_hop))
+                return "Next node: {0} is not a switch".format(next_hop)
+            else:
+                # take first link between switches by default
+                index_edge_out = 0
+                switch_outport_nr = self.DCNetwork_graph[current_hop][next_hop][index_edge_out]['src_port_nr']
+
+
+           # set of entry via ovs-ofctl
+            if isinstance( current_node, OVSSwitch ):
+                kwargs['vlan'] = tag
+                kwargs['path'] = path
+                kwargs['current_hop'] = current_hop
+                kwargs['switch_inport_name'] = src_sw_inport_name
+                kwargs['switch_outport_name'] = dst_sw_outport_name
+                kwargs['skip_vlan_tag'] = True
+
+                monitor_placement = kwargs.get('monitor_placement')
+                # put monitor flow at the dst switch
+                insert_flow = False
+                if monitor_placement == 'tx' and path.index(current_hop) == 0:  # first node:
+                    insert_flow = True
+                # put monitoring flow at the src switch
+                elif monitor_placement == 'rx' and path.index(current_hop) == len(path) - 1:  # last node:
+                    insert_flow = True
+                else:
+                    LOG.exception('invalid monitor command: {0}'.format(monitor_placement))
+
+
+                if self.controller == RemoteController and insert_flow:
+                    ## set flow entry via ryu rest api
+                    self._set_flow_entry_ryu_rest(current_node, switch_inport_nr, switch_outport_nr, **kwargs)
+                    break
+                elif insert_flow:
+                    ## set flow entry via ovs-ofctl
+                    self._set_flow_entry_dpctl(current_node, switch_inport_nr, switch_outport_nr, **kwargs)
+                    break
+
+            # take first link between switches by default
+            if isinstance( next_node, OVSSwitch ):
+                switch_inport_nr = self.DCNetwork_graph[current_hop][next_hop][0]['dst_port_nr']
+                current_hop = next_hop
+
+        return "path {2} between {0} and {1}".format(vnf_src_name, vnf_dst_name, cmd)
+
+
     def setChain(self, vnf_src_name, vnf_dst_name, vnf_src_interface=None, vnf_dst_interface=None, **kwargs):
         """
         Chain 2 vnf interfaces together by installing the flowrules in the switches along their path.
@@ -276,17 +487,37 @@
         :param priority: custom flowrule priority
         :return: output log string
         """
+
+        # special procedure for monitoring flows
+        if kwargs.get('monitor'):
+
+            # check if chain already exists
+            found_chains = [chain_dict for chain_dict in self.installed_chains if
+             (chain_dict['vnf_src_name'] == vnf_src_name and chain_dict['vnf_src_interface'] == vnf_src_interface
+             and chain_dict['vnf_dst_name'] == vnf_dst_name and chain_dict['vnf_dst_interface'] == vnf_dst_interface)]
+
+            if len(found_chains) > 0:
+                # this chain exists, so need an extra monitoring flow
+                # assume only 1 chain per vnf/interface pair
+                LOG.debug('*** installing monitoring chain on top of pre-defined chain from {0}:{1} -> {2}:{3}'.
+                            format(vnf_src_name, vnf_src_interface, vnf_dst_name, vnf_dst_interface))
+                tag = found_chains[0]['tag']
+                ret = self._addMonitorFlow(vnf_src_name, vnf_dst_name, vnf_src_interface, vnf_dst_interface,
+                                     tag=tag, table_id=0, **kwargs)
+                return ret
+            else:
+                # no chain existing (or E-LAN) -> install normal chain
+                LOG.warning('*** installing monitoring chain without pre-defined chain from {0}:{1} -> {2}:{3}'.
+                            format(vnf_src_name, vnf_src_interface, vnf_dst_name, vnf_dst_interface))
+                pass
+
+
         cmd = kwargs.get('cmd')
-        if cmd == 'add-flow':
+        if cmd == 'add-flow' or cmd == 'del-flows':
             ret = self._chainAddFlow(vnf_src_name, vnf_dst_name, vnf_src_interface, vnf_dst_interface, **kwargs)
             if kwargs.get('bidirectional'):
                 ret = ret +'\n' + self._chainAddFlow(vnf_dst_name, vnf_src_name, vnf_dst_interface, vnf_src_interface, **kwargs)
 
-        elif cmd == 'del-flows':
-            ret = self._chainAddFlow(vnf_src_name, vnf_dst_name, vnf_src_interface, vnf_dst_interface, **kwargs)
-            if kwargs.get('bidirectional'):
-                ret = ret + '\n' + self._chainAddFlow(vnf_dst_name, vnf_src_name, vnf_dst_interface, vnf_src_interface, **kwargs)
-
         else:
             ret = "Command unknown"
 
@@ -296,9 +527,11 @@
     def _chainAddFlow(self, vnf_src_name, vnf_dst_name, vnf_src_interface=None, vnf_dst_interface=None, **kwargs):
 
         src_sw = None
-        dst_sw = None
         src_sw_inport_nr = 0
+        src_sw_inport_name = None
+        dst_sw = None
         dst_sw_outport_nr = 0
+        dst_sw_outport_name = None
 
         LOG.debug("call chainAddFlow vnf_src_name=%r, vnf_src_interface=%r, vnf_dst_name=%r, vnf_dst_interface=%r",
                   vnf_src_name, vnf_src_interface, vnf_dst_name, vnf_dst_interface)
@@ -318,6 +551,7 @@
                     # found the right link and connected switch
                     src_sw = connected_sw
                     src_sw_inport_nr = link_dict[link]['dst_port_nr']
+                    src_sw_inport_name = link_dict[link]['dst_port_name']
                     break
 
         if vnf_dst_interface is None:
@@ -335,6 +569,7 @@
                     # found the right link and connected switch
                     dst_sw = connected_sw
                     dst_sw_outport_nr = link_dict[link]['src_port_nr']
+                    dst_sw_outport_name = link_dict[link]['src_port_name']
                     break
 
 
@@ -357,13 +592,28 @@
         current_hop = src_sw
         switch_inport_nr = src_sw_inport_nr
 
-        # choose free vlan if path contains more than 1 switch
+        # choose free vlan
+        ## if path contains more than 1 switch
         cmd = kwargs.get('cmd')
         vlan = None
         if cmd == 'add-flow':
-            if len(path) > 1:
+            if kwargs.get('tag'):
+                # use pre-defined tag
+                vlan = kwargs.get('tag')
+            else:
                 vlan = self.vlans.pop()
 
+        # store the used vlan tag to identify this chain
+        if not kwargs.get('monitor'):
+            chain_dict = {}
+            chain_dict['vnf_src_name'] = vnf_src_name
+            chain_dict['vnf_dst_name'] = vnf_dst_name
+            chain_dict['vnf_src_interface'] = vnf_src_interface
+            chain_dict['vnf_dst_interface'] = vnf_dst_interface
+            chain_dict['tag'] = vlan
+            self.installed_chains.append(chain_dict)
+
+        #iterate through the path to install the flow-entries
         for i in range(0,len(path)):
             current_node = self.getNodeByName(current_hop)
 
@@ -392,6 +642,8 @@
                 kwargs['vlan'] = vlan
                 kwargs['path'] = path
                 kwargs['current_hop'] = current_hop
+                kwargs['switch_inport_name'] = src_sw_inport_name
+                kwargs['switch_outport_name'] = dst_sw_outport_name
 
                 if self.controller == RemoteController:
                     ## set flow entry via ryu rest api
@@ -400,8 +652,6 @@
                     ## set flow entry via ovs-ofctl
                     self._set_flow_entry_dpctl(current_node, switch_inport_nr, switch_outport_nr, **kwargs)
 
-
-
             # take first link between switches by default
             if isinstance( next_node, OVSSwitch ):
                 switch_inport_nr = self.DCNetwork_graph[current_hop][next_hop][0]['dst_port_nr']
@@ -419,6 +669,12 @@
         current_hop = kwargs.get('current_hop')
         vlan = kwargs.get('vlan')
         priority = kwargs.get('priority')
+        # flag to not set the ovs port vlan tag
+        skip_vlan_tag = kwargs.get('skip_vlan_tag')
+        # table id to put this flowentry
+        table_id = kwargs.get('table_id')
+        if not table_id:
+            table_id = 0
 
         s = ','
         if match_input:
@@ -432,6 +688,8 @@
         if priority:
             flow['priority'] = int(priority)
 
+        flow['table_id'] = table_id
+
         flow['actions'] = []
 
         # possible Ryu actions, match fields:
@@ -440,22 +698,37 @@
             prefix = 'stats/flowentry/add'
             if vlan != None:
                 if path.index(current_hop) == 0:  # first node
-                    action = {}
-                    action['type'] = 'PUSH_VLAN'  # Push a new VLAN tag if a input frame is non-VLAN-tagged
-                    action['ethertype'] = 33024   # Ethertype 0x8100(=33024): IEEE 802.1Q VLAN-tagged frame
-                    flow['actions'].append(action)
-                    action = {}
-                    action['type'] = 'SET_FIELD'
-                    action['field'] = 'vlan_vid'
-                    action['value'] = vlan
-                    flow['actions'].append(action)
-                elif path.index(current_hop) == len(path) - 1:  # last node
+                    # set vlan tag in ovs instance (to isolate E-LANs)
+                    if not skip_vlan_tag:
+                        in_port_name = kwargs.get('switch_inport_name')
+                        self._set_vlan_tag(node, in_port_name, vlan)
+                    # set vlan push action if more than 1 switch in the path
+                    if len(path) > 1:
+                        action = {}
+                        action['type'] = 'PUSH_VLAN'  # Push a new VLAN tag if a input frame is non-VLAN-tagged
+                        action['ethertype'] = 33024   # Ethertype 0x8100(=33024): IEEE 802.1Q VLAN-tagged frame
+                        flow['actions'].append(action)
+                        action = {}
+                        action['type'] = 'SET_FIELD'
+                        action['field'] = 'vlan_vid'
+                        action['value'] = vlan
+                        flow['actions'].append(action)
+
+                if path.index(current_hop) == len(path) - 1:  # last node
+                    # set vlan tag in ovs instance (to isolate E-LANs)
+                    if not skip_vlan_tag:
+                        out_port_name = kwargs.get('switch_outport_name')
+                        self._set_vlan_tag(node, out_port_name, vlan)
+                    # set vlan pop action if more than 1 switch in the path
+                    if len(path) > 1:
+                        match += ',dl_vlan=%s' % vlan
+                        action = {}
+                        action['type'] = 'POP_VLAN'
+                        flow['actions'].append(action)
+
+                if 0 < path.index(current_hop) < (len(path) - 1):  # middle nodes
                     match += ',dl_vlan=%s' % vlan
-                    action = {}
-                    action['type'] = 'POP_VLAN'
-                    flow['actions'].append(action)
-                else:  # middle nodes
-                    match += ',dl_vlan=%s' % vlan
+
             # output action must come last
             action = {}
             action['type'] = 'OUTPUT'
@@ -477,7 +750,12 @@
         flow['match'] = self._parse_match(match)
         self.ryu_REST(prefix, data=flow)
 
+    def _set_vlan_tag(self, node, switch_port, tag):
+        node.vsctl('set', 'port {0} tag={1}'.format(switch_port,tag))
+        LOG.debug("set vlan in switch: {0} in_port: {1} vlan tag: {2}".format(node.name, switch_port, tag))
+
     def _set_flow_entry_dpctl(self, node, switch_inport_nr, switch_outport_nr, **kwargs):
+
         match = 'in_port=%s' % switch_inport_nr
 
         cookie = kwargs.get('cookie')
@@ -518,7 +796,11 @@
     def startRyu(self, learning_switch=True):
         # start Ryu controller with rest-API
         python_install_path = site.getsitepackages()[0]
-        ryu_path = python_install_path + '/ryu/app/simple_switch_13.py'
+        # ryu default learning switch
+        #ryu_path = python_install_path + '/ryu/app/simple_switch_13.py'
+        #custom learning switch that installs a default NORMAL action in the ovs switches
+        dir_path = os.path.dirname(os.path.realpath(__file__))
+        ryu_path = dir_path + '/son_emu_simple_switch_13.py'
         ryu_path2 = python_install_path + '/ryu/app/ofctl_rest.py'
         # change the default Openflow controller port to 6653 (official IANA-assigned port number), as used by Mininet
         # Ryu still uses 6633 as default
@@ -528,9 +810,12 @@
         FNULL = open("/tmp/ryu.log", 'w')
         if learning_switch:
             self.ryu_process = Popen([ryu_cmd, ryu_path, ryu_path2, ryu_option, ryu_of_port], stdout=FNULL, stderr=FNULL)
+            LOG.debug('starting ryu-controller with {0}'.format(ryu_path))
+            LOG.debug('starting ryu-controller with {0}'.format(ryu_path2))
         else:
             # no learning switch, but with rest api
             self.ryu_process = Popen([ryu_cmd, ryu_path2, ryu_option, ryu_of_port], stdout=FNULL, stderr=FNULL)
+            LOG.debug('starting ryu-controller with {0}'.format(ryu_path2))
         time.sleep(1)
 
     def killRyu(self):
@@ -592,3 +877,14 @@
                 dict.update({match[0]:m2})
         return dict
 
+    def find_connected_dc_interface(self, vnf_src_name, vnf_src_interface):
+        for connected_sw in self.DCNetwork_graph.neighbors(vnf_src_name):
+            link_dict = self.DCNetwork_graph[vnf_src_name][connected_sw]
+            for link in link_dict:
+                if (link_dict[link]['src_port_id'] == vnf_src_interface or
+                        link_dict[link]['src_port_name'] == vnf_src_interface):  # Fix: we might also get interface names, e.g, from a son-emu-cli call
+                    # found the right link and connected switch
+                    src_sw = connected_sw
+                    src_sw_inport_nr = link_dict[link]['dst_port_nr']
+                    src_sw_inport_name = link_dict[link]['dst_port_name']
+                    return src_sw_inport_name
\ No newline at end of file
diff --git a/src/emuvim/dcemulator/node.py b/src/emuvim/dcemulator/node.py
index b88913b..8219761 100755
--- a/src/emuvim/dcemulator/node.py
+++ b/src/emuvim/dcemulator/node.py
@@ -61,9 +61,17 @@
         Helper method to receive information about the virtual networks
         this compute instance is connected to.
         """
-        # format list of tuples (name, Ip, MAC, isUp, status)
-        return [{'intf_name':str(i), 'ip':i.IP(), 'mac':i.MAC(), 'up':i.isUp(), 'status':i.status()}
-                for i in self.intfList()]
+        # get all links and find dc switch interface
+        networkStatusList = []
+        for i in self.intfList():
+            vnf_name = self.name
+            vnf_interface = str(i)
+            dc_port_name = self.datacenter.net.find_connected_dc_interface(vnf_name, vnf_interface)
+            # format list of tuples (name, Ip, MAC, isUp, status, dc_portname)
+            intf_dict = {'intf_name': str(i), 'ip': i.IP(), 'mac': i.MAC(), 'up': i.isUp(), 'status': i.status(), 'dc_portname': dc_port_name}
+            networkStatusList.append(intf_dict)
+
+        return networkStatusList
 
     def getStatus(self):
         """
diff --git a/src/emuvim/dcemulator/son_emu_simple_switch_13.py b/src/emuvim/dcemulator/son_emu_simple_switch_13.py
new file mode 100755
index 0000000..53d1a2e
--- /dev/null
+++ b/src/emuvim/dcemulator/son_emu_simple_switch_13.py
@@ -0,0 +1,134 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+#
+# 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 ryu.base import app_manager
+from ryu.controller import ofp_event
+from ryu.controller.handler import CONFIG_DISPATCHER, MAIN_DISPATCHER
+from ryu.controller.handler import set_ev_cls
+from ryu.ofproto import ofproto_v1_3
+from ryu.lib.packet import packet
+from ryu.lib.packet import ethernet
+from ryu.lib.packet import ether_types
+from ryu.topology.event import EventSwitchEnter, EventSwitchLeave, EventSwitchReconnected
+
+class SimpleSwitch13(app_manager.RyuApp):
+    OFP_VERSIONS = [ofproto_v1_3.OFP_VERSION]
+
+    def __init__(self, *args, **kwargs):
+        super(SimpleSwitch13, self).__init__(*args, **kwargs)
+        self.mac_to_port = {}
+
+    @set_ev_cls(ofp_event.EventOFPSwitchFeatures, CONFIG_DISPATCHER)
+    def switch_features_handler(self, ev):
+        datapath = ev.msg.datapath
+        ofproto = datapath.ofproto
+        parser = datapath.ofproto_parser
+
+        # install table-miss flow entry
+        #
+        # We specify NO BUFFER to max_len of the output action due to
+        # OVS bug. At this moment, if we specify a lesser number, e.g.,
+        # 128, OVS will send Packet-In with invalid buffer_id and
+        # truncated packet data. In that case, we cannot output packets
+        # correctly.  The bug has been fixed in OVS v2.1.0.
+        match = parser.OFPMatch()
+        #actions = [parser.OFPActionOutput(ofproto.OFPP_CONTROLLER,
+        #                                  ofproto.OFPCML_NO_BUFFER)]
+        actions = [parser.OFPActionOutput(ofproto.OFPCML_NO_BUFFER)]
+        self.add_flow(datapath, 0, match, actions)
+
+    def add_flow(self, datapath, priority, match, actions, buffer_id=None, table_id=0):
+        ofproto = datapath.ofproto
+        parser = datapath.ofproto_parser
+
+        inst = [parser.OFPInstructionActions(ofproto.OFPIT_APPLY_ACTIONS,
+                                             actions)]
+        if buffer_id:
+            mod = parser.OFPFlowMod(datapath=datapath, buffer_id=buffer_id,
+                                    priority=priority, match=match,
+                                    instructions=inst, table_id=table_id)
+        else:
+            mod = parser.OFPFlowMod(datapath=datapath, priority=priority,
+                                    match=match, instructions=inst, table_id=table_id)
+        datapath.send_msg(mod)
+
+        # new switch detected
+
+    @set_ev_cls([EventSwitchEnter, EventSwitchReconnected])
+    def _ev_switch_enter_handler(self, ev):
+        datapath = ev.switch.dp
+        self.logger.info('registered OF switch id: %s' % datapath.id)
+        ofproto = datapath.ofproto
+        self.logger.info('OF version: {0}'.format(ofproto))
+        # send NORMAL action for all undefined flows
+        ofp_parser = datapath.ofproto_parser
+        actions = [ofp_parser.OFPActionOutput(ofproto_v1_3.OFPP_NORMAL)]
+        self.add_flow(datapath, 0, None, actions, table_id=0)
+
+
+    @set_ev_cls(ofp_event.EventOFPPacketIn, MAIN_DISPATCHER)
+    def _packet_in_handler(self, ev):
+        # If you hit this you might want to increase
+        # the "miss_send_length" of your switch
+        if ev.msg.msg_len < ev.msg.total_len:
+            self.logger.debug("packet truncated: only %s of %s bytes",
+                              ev.msg.msg_len, ev.msg.total_len)
+        msg = ev.msg
+        datapath = msg.datapath
+        ofproto = datapath.ofproto
+        parser = datapath.ofproto_parser
+        in_port = msg.match['in_port']
+
+        pkt = packet.Packet(msg.data)
+        eth = pkt.get_protocols(ethernet.ethernet)[0]
+
+        if eth.ethertype == ether_types.ETH_TYPE_LLDP:
+            # ignore lldp packet
+            return
+        dst = eth.dst
+        src = eth.src
+
+        dpid = datapath.id
+        self.mac_to_port.setdefault(dpid, {})
+
+        self.logger.info("packet in %s %s %s %s", dpid, src, dst, in_port)
+
+        # learn a mac address to avoid FLOOD next time.
+        self.mac_to_port[dpid][src] = in_port
+
+        if dst in self.mac_to_port[dpid]:
+            out_port = self.mac_to_port[dpid][dst]
+        else:
+            out_port = ofproto.OFPP_FLOOD
+
+        actions = [parser.OFPActionOutput(out_port)]
+
+        # install a flow to avoid packet_in next time
+        if out_port != ofproto.OFPP_FLOOD:
+            match = parser.OFPMatch(in_port=in_port, eth_dst=dst)
+            # verify if we have a valid buffer_id, if yes avoid to send both
+            # flow_mod & packet_out
+            if msg.buffer_id != ofproto.OFP_NO_BUFFER:
+                self.add_flow(datapath, 1, match, actions, msg.buffer_id)
+                return
+            else:
+                self.add_flow(datapath, 1, match, actions)
+        data = None
+        if msg.buffer_id == ofproto.OFP_NO_BUFFER:
+            data = msg.data
+
+        out = parser.OFPPacketOut(datapath=datapath, buffer_id=msg.buffer_id,
+                                  in_port=in_port, actions=actions, data=data)
+        datapath.send_msg(out)
diff --git a/src/emuvim/examples/sonata_y1_demo_topology_1_w_ls_and_mon_and_sap.py b/src/emuvim/examples/sonata_y1_demo_topology_1_w_ls_and_mon_and_sap.py
old mode 100644
new mode 100755
index df7a6ac..b38720e
--- a/src/emuvim/examples/sonata_y1_demo_topology_1_w_ls_and_mon_and_sap.py
+++ b/src/emuvim/examples/sonata_y1_demo_topology_1_w_ls_and_mon_and_sap.py
@@ -46,7 +46,7 @@
 
 def create_topology1():
     # create topology
-    net = DCNetwork(controller=RemoteController, monitor=True, enable_learning=False)
+    net = DCNetwork(controller=RemoteController, monitor=True, enable_learning=True)
     dc1 = net.addDatacenter("dc1")
     dc2 = net.addDatacenter("dc2")
     s1 = net.addSwitch("s1")
diff --git a/src/emuvim/examples/sonata_y1_demo_topology_1_w_ls_and_sap.py b/src/emuvim/examples/sonata_y1_demo_topology_1_w_ls_and_sap.py
old mode 100644
new mode 100755