Cleanup: Environment cleanup mechanisms. Closes #139

[osm/vim-emu.git] / src / emuvim / dcemulator / net.py

diff --git a/src/emuvim/dcemulator/net.py b/src/emuvim/dcemulator/net.py
index da546ab..cbe668f 100755 (executable)
--- a/src/emuvim/dcemulator/net.py
+++ b/src/emuvim/dcemulator/net.py
@@ -1,71 +1,124 @@
 """
 """

-Distributed Cloud Emulator (dcemulator)
-(c) 2015 by Manuel Peuster <manuel.peuster@upb.de>
+Copyright (c) 2015 SONATA-NFV and Paderborn University
+ALL RIGHTS RESERVED.
+
+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.
+
+Neither the name of the SONATA-NFV [, ANY ADDITIONAL AFFILIATION]
+nor the names of its contributors may be used to endorse or promote
+products derived from this software without specific prior written
+permission.
+
+This work has been performed in the framework of the SONATA project,
+funded by the European Commission under Grant number 671517 through
+the Horizon 2020 and 5G-PPP programmes. The authors would like to
+acknowledge the contributions of their colleagues of the SONATA
+partner consortium (www.sonata-nfv.eu).

 """
 import logging
 
 import site
 """
 import logging
 
 import site

+import time

 from subprocess import Popen
 import os
 from subprocess import Popen
 import os

+import re
+import urllib2
+from functools import partial

 
 

-from mininet.net import Dockernet
-from mininet.node import Controller, OVSSwitch, OVSKernelSwitch, Switch, Docker, Host, RemoteController
+from mininet.net import Containernet
+from mininet.node import Controller, DefaultController, OVSSwitch, OVSKernelSwitch, Docker, RemoteController

 from mininet.cli import CLI
 from mininet.cli import CLI

-from mininet.log import setLogLevel, info, debug

 from mininet.link import TCLink
 from mininet.link import TCLink

+from mininet.clean import cleanup

 import networkx as nx
 from emuvim.dcemulator.monitoring import DCNetworkMonitor
 from emuvim.dcemulator.node import Datacenter, EmulatorCompute
 from emuvim.dcemulator.resourcemodel import ResourceModelRegistrar
 
 import networkx as nx
 from emuvim.dcemulator.monitoring import DCNetworkMonitor
 from emuvim.dcemulator.node import Datacenter, EmulatorCompute
 from emuvim.dcemulator.resourcemodel import ResourceModelRegistrar
 

+LOG = logging.getLogger("dcemulator.net")
+LOG.setLevel(logging.DEBUG)

 
 

-class DCNetwork(Dockernet):
+class DCNetwork(Containernet):

     """
     """

-    Wraps the original Mininet/Dockernet class and provides
+    Wraps the original Mininet/Containernet class and provides

     methods to add data centers, switches, etc.
 
     This class is used by topology definition scripts.
     """
 
     methods to add data centers, switches, etc.
 
     This class is used by topology definition scripts.
     """
 

-    def __init__(self, dc_emulation_max_cpu=1.0, **kwargs):
+    def __init__(self, controller=RemoteController, monitor=False,
+                 enable_learning = True,   # in case of RemoteController (Ryu), learning switch behavior can be turned off/on
+                 dc_emulation_max_cpu=1.0,  # fraction of overall CPU time for emulation
+                 dc_emulation_max_mem=512,  # emulation max mem in MB
+                 **kwargs):

         """
         """

-        Create an extended version of a Dockernet network
+        Create an extended version of a Containernet network

         :param dc_emulation_max_cpu: max. CPU time used by containers in data centers
         :param kwargs: path through for Mininet parameters
         :return:
         """
         :param dc_emulation_max_cpu: max. CPU time used by containers in data centers
         :param kwargs: path through for Mininet parameters
         :return:
         """

+        # members

         self.dcs = {}
         self.dcs = {}

+        self.ryu_process = None
+
+        # always cleanup environment before we start the emulator
+        self.killRyu()
+        cleanup()

 
         # call original Docker.__init__ and setup default controller
 
         # call original Docker.__init__ and setup default controller

-        Dockernet.__init__(
-            self, controller=RemoteController, switch=OVSKernelSwitch, **kwargs)
+        Containernet.__init__(
+            self, switch=OVSKernelSwitch, controller=controller, **kwargs)
+
+        # Ryu management
+        if controller == RemoteController:
+            # start Ryu controller
+            self.startRyu(learning_switch=enable_learning)

 
 

-        # ass a remote controller to be able to use Ryu
-        self.addController('c0', controller=RemoteController)
+        # add the specified controller
+        self.addController('c0', controller=controller)

 
         # graph of the complete DC network
 
         # graph of the complete DC network

-        self.DCNetwork_graph=nx.DiGraph()
+        self.DCNetwork_graph = nx.MultiDiGraph()

 
 

-        # monitoring agent
-        self.monitor_agent = DCNetworkMonitor(self)
+        # initialize pool of vlan tags to setup the SDN paths
+        self.vlans = range(4096)[::-1]

 
 

-        # start Ryu controller
-        self.startRyu()
+        # link to Ryu REST_API
+        ryu_ip = '0.0.0.0'
+        ryu_port = '8080'
+        self.ryu_REST_api = 'http://{0}:{1}'.format(ryu_ip, ryu_port)
+
+        # monitoring agent
+        if monitor:
+            self.monitor_agent = DCNetworkMonitor(self)
+        else:
+            self.monitor_agent = None

 
         # initialize resource model registrar
 
         # initialize resource model registrar

-        self.rm_registrar = ResourceModelRegistrar(dc_emulation_max_cpu)
+        self.rm_registrar = ResourceModelRegistrar(
+            dc_emulation_max_cpu, dc_emulation_max_mem)

 
 

-    def addDatacenter(self, label, metadata={}):
+    def addDatacenter(self, label, metadata={}, resource_log_path=None):

         """
         Create and add a logical cloud data center to the network.
         """
         if label in self.dcs:
             raise Exception("Data center label already exists: %s" % label)
         """
         Create and add a logical cloud data center to the network.
         """
         if label in self.dcs:
             raise Exception("Data center label already exists: %s" % label)

-        dc = Datacenter(label, metadata=metadata)
+        dc = Datacenter(label, metadata=metadata, resource_log_path=resource_log_path)

         dc.net = self  # set reference to network
         self.dcs[label] = dc
         dc.create()  # finally create the data center in our Mininet instance
         dc.net = self  # set reference to network
         self.dcs[label] = dc
         dc.create()  # finally create the data center in our Mininet instance

-        logging.info("added data center: %s" % label)
+        LOG.info("added data center: %s" % label)

         return dc
 
     def addLink(self, node1, node2, **params):
         return dc
 
     def addLink(self, node1, node2, **params):


@@ -75,7 +128,7 @@ class DCNetwork(Dockernet):
         """
         assert node1 is not None
         assert node2 is not None
         """
         assert node1 is not None
         assert node2 is not None

-        logging.debug("addLink: n1=%s n2=%s" % (str(node1), str(node2)))
+        LOG.debug("addLink: n1=%s n2=%s" % (str(node1), str(node2)))

         # ensure type of node1
         if isinstance( node1, basestring ):
             if node1 in self.dcs:
         # ensure type of node1
         if isinstance( node1, basestring ):
             if node1 in self.dcs:


@@ -101,17 +154,57 @@ class DCNetwork(Dockernet):
                 params["params2"]["ip"] = self.getNextIp()
         # ensure that we allow TCLinks between data centers
         # TODO this is not optimal, we use cls=Link for containers and TCLink for data centers
                 params["params2"]["ip"] = self.getNextIp()
         # ensure that we allow TCLinks between data centers
         # TODO this is not optimal, we use cls=Link for containers and TCLink for data centers

-        # see Dockernet issue: https://github.com/mpeuster/dockernet/issues/3
+        # see Containernet issue: https://github.com/mpeuster/containernet/issues/3

         if "cls" not in params:
             params["cls"] = TCLink
 
         if "cls" not in params:
             params["cls"] = TCLink
 

-        link = Dockernet.addLink(self, node1, node2, **params)
+        link = Containernet.addLink(self, node1, node2, **params)
+
+        # try to give container interfaces a default id
+        node1_port_id = node1.ports[link.intf1]
+        if isinstance(node1, Docker):
+            if "id" in params["params1"]:
+                node1_port_id = params["params1"]["id"]
+        node1_port_name = link.intf1.name
+
+        node2_port_id = node2.ports[link.intf2]
+        if isinstance(node2, Docker):
+            if "id" in params["params2"]:
+                node2_port_id = params["params2"]["id"]
+        node2_port_name = link.intf2.name
+

 
         # add edge and assigned port number to graph in both directions between node1 and node2
 
         # add edge and assigned port number to graph in both directions between node1 and node2

-        self.DCNetwork_graph.add_edge(node1.name, node2.name, \
-                                      {'src_port': node1.ports[link.intf1], 'dst_port': node2.ports[link.intf2]})
-        self.DCNetwork_graph.add_edge(node2.name, node1.name, \
-                                       {'src_port': node2.ports[link.intf2], 'dst_port': node1.ports[link.intf1]})
+        # port_id: id given in descriptor (if available, otherwise same as port)
+        # port: portnumber assigned by Containernet
+
+        attr_dict = {}
+        # possible weight metrics allowed by TClink class:
+        weight_metrics = ['bw', 'delay', 'jitter', 'loss']
+        edge_attributes = [p for p in params if p in weight_metrics]
+        for attr in edge_attributes:
+            # if delay: strip ms (need number as weight in graph)
+            match = re.search('([0-9]*\.?[0-9]+)', params[attr])
+            if match:
+                attr_number = match.group(1)
+            else:
+                attr_number = None
+            attr_dict[attr] = attr_number
+
+
+        attr_dict2 = {'src_port_id': node1_port_id, 'src_port_nr': node1.ports[link.intf1],
+                      'src_port_name': node1_port_name,
+                     'dst_port_id': node2_port_id, 'dst_port_nr': node2.ports[link.intf2],
+                      'dst_port_name': node2_port_name}
+        attr_dict2.update(attr_dict)
+        self.DCNetwork_graph.add_edge(node1.name, node2.name, attr_dict=attr_dict2)
+
+        attr_dict2 = {'src_port_id': node2_port_id, 'src_port_nr': node2.ports[link.intf2],
+                      'src_port_name': node2_port_name,
+                     'dst_port_id': node1_port_id, 'dst_port_nr': node1.ports[link.intf1],
+                      'dst_port_name': node1_port_name}
+        attr_dict2.update(attr_dict)
+        self.DCNetwork_graph.add_edge(node2.name, node1.name, attr_dict=attr_dict2)

 
         return link
 
 
         return link
 


@@ -120,14 +213,14 @@ class DCNetwork(Dockernet):
         Wrapper for addDocker method to use custom container class.
         """
         self.DCNetwork_graph.add_node(label)
         Wrapper for addDocker method to use custom container class.
         """
         self.DCNetwork_graph.add_node(label)

-        return Dockernet.addDocker(self, label, cls=EmulatorCompute, **params)
+        return Containernet.addDocker(self, label, cls=EmulatorCompute, **params)

 
     def removeDocker( self, label, **params ):
         """
         Wrapper for removeDocker method to update graph.
         """
         self.DCNetwork_graph.remove_node(label)
 
     def removeDocker( self, label, **params ):
         """
         Wrapper for removeDocker method to update graph.
         """
         self.DCNetwork_graph.remove_node(label)

-        return Dockernet.removeDocker(self, label, **params)
+        return Containernet.removeDocker(self, label, **params)

 
     def addSwitch( self, name, add_to_graph=True, **params ):
         """
 
     def addSwitch( self, name, add_to_graph=True, **params ):
         """


@@ -135,7 +228,7 @@ class DCNetwork(Dockernet):
         """
         if add_to_graph:
             self.DCNetwork_graph.add_node(name)
         """
         if add_to_graph:
             self.DCNetwork_graph.add_node(name)

-        return Dockernet.addSwitch(self, name, protocols='OpenFlow10,OpenFlow12,OpenFlow13', **params)
+        return Containernet.addSwitch(self, name, protocols='OpenFlow10,OpenFlow12,OpenFlow13', **params)

 
     def getAllContainers(self):
         """
 
     def getAllContainers(self):
         """


@@ -150,70 +243,324 @@ class DCNetwork(Dockernet):
         # start
         for dc in self.dcs.itervalues():
             dc.start()
         # start
         for dc in self.dcs.itervalues():
             dc.start()

-        Dockernet.start(self)
+        Containernet.start(self)

 
     def stop(self):
 
     def stop(self):

+
+        # stop the monitor agent
+        if self.monitor_agent is not None:
+            self.monitor_agent.stop()
+
+        # stop emulator net
+        Containernet.stop(self)
+

         # stop Ryu controller
         # stop Ryu controller

-        self.ryu_process.terminate()
-        #self.ryu_process.kill()
-        Dockernet.stop(self)
+        self.killRyu()
+

 
     def CLI(self):
         CLI(self)
 
     # to remove chain do setChain( src, dst, cmd='del-flows')
 
     def CLI(self):
         CLI(self)
 
     # to remove chain do setChain( src, dst, cmd='del-flows')

-    def setChain(self, vnf_src_name, vnf_dst_name, cmd='add-flow'):
+    def setChain(self, vnf_src_name, vnf_dst_name, vnf_src_interface=None, vnf_dst_interface=None, **kwargs):
+        cmd = kwargs.get('cmd')
+        if cmd == 'add-flow':
+            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"
+
+        return ret
+
+
+    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
+        dst_sw_outport_nr = 0
+
+        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)
+
+        #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']
+                    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']
+                    break
+
+

         # get shortest path
         # get shortest path

-        path = nx.shortest_path(self.DCNetwork_graph, vnf_src_name, vnf_dst_name)
-        logging.info("Path between {0} and {1}: {2}".format(vnf_src_name, vnf_dst_name, 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
+
+        # choose free vlan if path contains more than 1 switch
+        cmd = kwargs.get('cmd')
+        vlan = None
+        if cmd == 'add-flow':
+            if len(path) > 1:
+                vlan = self.vlans.pop()

 
 

-        current_hop = vnf_src_name

         for i in range(0,len(path)):
         for i in range(0,len(path)):

-            next_hop = path[path.index(current_hop)+1]
+            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:
             next_node = self.getNodeByName(next_hop)
 
             if next_hop == vnf_dst_name:

-                return "path added between {0} and {1}".format(vnf_src_name, 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 ):
             elif not isinstance( next_node, OVSSwitch ):

-                logging.info("Next node: {0} is not a switch".format(next_hop))
+                LOG.info("Next node: {0} is not a switch".format(next_hop))

                 return "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']

 
 
 
 

-            switch_inport = self.DCNetwork_graph[current_hop][next_hop]['dst_port']
-            next2_hop = path[path.index(current_hop)+2]
-            switch_outport = self.DCNetwork_graph[next_hop][next2_hop]['src_port']
+           # set of entry via ovs-ofctl
+            if isinstance( current_node, OVSSwitch ):
+                kwargs['vlan'] = vlan
+                kwargs['path'] = path
+                kwargs['current_hop'] = current_hop

 
 

-            logging.info("add flow in switch: {0} in_port: {1} out_port: {2}".format(next_node.name, switch_inport, switch_outport))
-            # set of entry via ovs-ofctl
-            # TODO use rest API of ryu to set flow entries to correct witch dpid
-            if isinstance( next_node, OVSSwitch ):
-                match = 'in_port=%s' % switch_inport
-
-                if cmd=='add-flow':
-                    action = 'action=%s' % switch_outport
-                    s = ','
-                    ofcmd = s.join([match,action])
-                elif cmd=='del-flows':
-                    ofcmd = match
+                if self.controller == RemoteController:
+                    ## set flow entry via ryu rest api
+                    self._set_flow_entry_ryu_rest(current_node, switch_inport_nr, switch_outport_nr, **kwargs)

                 else:
                 else:

-                    ofcmd=''
+                    ## set flow entry via ovs-ofctl
+                    self._set_flow_entry_dpctl(current_node, switch_inport_nr, switch_outport_nr, **kwargs)

 
 

-                next_node.dpctl(cmd, ofcmd)

 
 

-            current_hop = next_hop

 
 

-        return "destination node: {0} not reached".format(vnf_dst_name)
+            # 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 _set_flow_entry_ryu_rest(self, node, switch_inport_nr, switch_outport_nr, **kwargs):
+        match = 'in_port=%s' % switch_inport_nr
+
+        cookie = kwargs.get('cookie')
+        match_input = kwargs.get('match')
+        cmd = kwargs.get('cmd')
+        path = kwargs.get('path')
+        current_hop = kwargs.get('current_hop')
+        vlan = kwargs.get('vlan')
+
+        s = ','
+        if match_input:
+            match = s.join([match, match_input])
+
+        flow = {}
+        flow['dpid'] = int(node.dpid, 16)
+
+        if cookie:
+            flow['cookie'] = int(cookie)
+
+
+        flow['actions'] = []
+
+        # possible Ryu actions, match fields:
+        # http://ryu.readthedocs.io/en/latest/app/ofctl_rest.html#add-a-flow-entry
+        if cmd == 'add-flow':
+            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
+                    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'
+            action['port'] = switch_outport_nr
+            flow['actions'].append(action)
+
+        elif cmd == 'del-flows':
+            prefix = 'stats/flowentry/delete'
+
+            if cookie:
+                # TODO: add cookie_mask as argument
+                flow['cookie_mask'] = int('0xffffffffffffffff', 16)  # need full mask to match complete cookie
+
+            action = {}
+            action['type'] = 'OUTPUT'
+            action['port'] = switch_outport_nr
+            flow['actions'].append(action)
+
+        flow['match'] = self._parse_match(match)
+        self.ryu_REST(prefix, data=flow)
+
+    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')
+        match_input = kwargs.get('match')
+        cmd = kwargs.get('cmd')
+        path = kwargs.get('path')
+        current_hop = kwargs.get('current_hop')
+        vlan = kwargs.get('vlan')
+
+        s = ','
+        if cookie:
+            cookie = 'cookie=%s' % cookie
+            match = s.join([cookie, match])
+        if match_input:
+            match = s.join([match, match_input])
+        if cmd == 'add-flow':
+            action = 'action=%s' % switch_outport_nr
+            if vlan != None:
+                if path.index(current_hop) == 0:  # first node
+                    action = ('action=mod_vlan_vid:%s' % vlan) + (',output=%s' % switch_outport_nr)
+                    match = '-O OpenFlow13 ' + match
+                elif path.index(current_hop) == len(path) - 1:  # last node
+                    match += ',dl_vlan=%s' % vlan
+                    action = 'action=strip_vlan,output=%s' % switch_outport_nr
+                else:  # middle nodes
+                    match += ',dl_vlan=%s' % vlan
+            ofcmd = s.join([match, action])
+        elif cmd == 'del-flows':
+            ofcmd = match
+        else:
+            ofcmd = ''
+
+        node.dpctl(cmd, ofcmd)
+        LOG.info("{3} in switch: {0} in_port: {1} out_port: {2}".format(node.name, switch_inport_nr,
+                                                                                 switch_outport_nr, cmd))

 
     # start Ryu Openflow controller as Remote Controller for the DCNetwork
 
     # start Ryu Openflow controller as Remote Controller for the DCNetwork

-    def startRyu(self):
+    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'
         # start Ryu controller with rest-API
         python_install_path = site.getsitepackages()[0]
         ryu_path = python_install_path + '/ryu/app/simple_switch_13.py'

-        ryu_path2 =  python_install_path + '/ryu/app/ofctl_rest.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
         ryu_option = '--ofp-tcp-listen-port'
         ryu_of_port = '6653'
         # change the default Openflow controller port to 6653 (official IANA-assigned port number), as used by Mininet
         # Ryu still uses 6633 as default
         ryu_option = '--ofp-tcp-listen-port'
         ryu_of_port = '6653'

-        ryu_cmd =  'ryu-manager'
-        FNULL = open(os.devnull, 'w')
-        self.ryu_process = Popen([ryu_cmd, ryu_path, ryu_path2, ryu_option, ryu_of_port], stdout=FNULL, stderr=FNULL)
\ No newline at end of file
+        ryu_cmd = 'ryu-manager'
+        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)
+        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)
+        time.sleep(1)
+
+    def killRyu(self):
+        """
+        Stop the Ryu controller that might be started by son-emu.
+        :return:
+        """
+        # try it nicely
+        if self.ryu_process is not None:
+            self.ryu_process.terminate()
+            self.ryu_process.kill()
+        # ensure its death ;-)
+        Popen(['pkill', '-f', 'ryu-manager'])
+
+    def ryu_REST(self, prefix, dpid=None, data=None):
+        try:
+            if dpid:
+                url = self.ryu_REST_api + '/' + str(prefix) + '/' + str(dpid)
+            else:
+                url = self.ryu_REST_api + '/' + str(prefix)
+            if data:
+                #LOG.info('POST: {0}'.format(str(data)))
+                req = urllib2.Request(url, str(data))
+            else:
+                req = urllib2.Request(url)
+
+            ret = urllib2.urlopen(req).read()
+            return ret
+        except:
+            LOG.info('error url: {0}'.format(str(url)))
+            if data: LOG.info('error POST: {0}'.format(str(data)))
+
+    # need to respect that some match fields must be integers
+    # http://ryu.readthedocs.io/en/latest/app/ofctl_rest.html#description-of-match-and-actions
+    def _parse_match(self, match):
+        matches = match.split(',')
+        dict = {}
+        for m in matches:
+            match = m.split('=')
+            if len(match) == 2:
+                try:
+                    m2 = int(match[1], 0)
+                except:
+                    m2 = match[1]
+
+                dict.update({match[0]:m2})
+        return dict
+