diff --git a/apps/kubevirt-networking/api/src/main/java/org/onosproject/kubevirtnetworking/api/DefaultKubevirtNetwork.java b/apps/kubevirt-networking/api/src/main/java/org/onosproject/kubevirtnetworking/api/DefaultKubevirtNetwork.java
index 97808bb..970c0eb 100644
--- a/apps/kubevirt-networking/api/src/main/java/org/onosproject/kubevirtnetworking/api/DefaultKubevirtNetwork.java
+++ b/apps/kubevirt-networking/api/src/main/java/org/onosproject/kubevirtnetworking/api/DefaultKubevirtNetwork.java
@@ -107,7 +107,11 @@
 
     @Override
     public Set<KubevirtHostRoute> hostRoutes() {
-        return ImmutableSet.copyOf(hostRoutes);
+        if (hostRoutes == null || hostRoutes.size() == 0) {
+            return ImmutableSet.of();
+        } else {
+            return ImmutableSet.copyOf(hostRoutes);
+        }
     }
 
     @Override
diff --git a/apps/kubevirt-networking/app/src/main/java/org/onosproject/kubevirtnetworking/impl/NetworkAttachmentDefinitionWatcher.java b/apps/kubevirt-networking/app/src/main/java/org/onosproject/kubevirtnetworking/impl/NetworkAttachmentDefinitionWatcher.java
new file mode 100644
index 0000000..291db11
--- /dev/null
+++ b/apps/kubevirt-networking/app/src/main/java/org/onosproject/kubevirtnetworking/impl/NetworkAttachmentDefinitionWatcher.java
@@ -0,0 +1,297 @@
+/*
+ * Copyright 2021-present Open Networking Foundation
+ *
+ * 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.
+ */
+package org.onosproject.kubevirtnetworking.impl;
+
+import io.fabric8.kubernetes.client.KubernetesClient;
+import io.fabric8.kubernetes.client.Watcher;
+import io.fabric8.kubernetes.client.WatcherException;
+import io.fabric8.kubernetes.client.dsl.base.CustomResourceDefinitionContext;
+import org.json.JSONException;
+import org.json.JSONObject;
+import org.onlab.packet.IpAddress;
+import org.onosproject.cluster.ClusterService;
+import org.onosproject.cluster.LeadershipService;
+import org.onosproject.cluster.NodeId;
+import org.onosproject.core.ApplicationId;
+import org.onosproject.core.CoreService;
+import org.onosproject.kubevirtnetworking.api.DefaultKubevirtNetwork;
+import org.onosproject.kubevirtnetworking.api.KubevirtIpPool;
+import org.onosproject.kubevirtnetworking.api.KubevirtNetwork;
+import org.onosproject.kubevirtnetworking.api.KubevirtNetwork.Type;
+import org.onosproject.kubevirtnetworking.api.KubevirtNetworkAdminService;
+import org.onosproject.kubevirtnode.api.KubevirtApiConfigEvent;
+import org.onosproject.kubevirtnode.api.KubevirtApiConfigListener;
+import org.onosproject.kubevirtnode.api.KubevirtApiConfigService;
+import org.onosproject.mastership.MastershipService;
+import org.osgi.service.component.annotations.Activate;
+import org.osgi.service.component.annotations.Component;
+import org.osgi.service.component.annotations.Deactivate;
+import org.osgi.service.component.annotations.Reference;
+import org.osgi.service.component.annotations.ReferenceCardinality;
+import org.slf4j.Logger;
+
+import java.io.IOException;
+import java.util.Objects;
+import java.util.concurrent.ExecutorService;
+
+import static java.util.concurrent.Executors.newSingleThreadExecutor;
+import static org.onlab.util.Tools.groupedThreads;
+import static org.onosproject.kubevirtnetworking.api.Constants.KUBEVIRT_NETWORKING_APP_ID;
+import static org.onosproject.kubevirtnetworking.api.KubevirtNetwork.Type.FLAT;
+import static org.onosproject.kubevirtnetworking.util.KubevirtNetworkingUtil.k8sClient;
+import static org.slf4j.LoggerFactory.getLogger;
+
+/**
+ * Kubernetes network-attachment-definition watcher used for feeding kubevirt network information.
+ */
+@Component(immediate = true)
+public class NetworkAttachmentDefinitionWatcher {
+
+    private final Logger log = getLogger(getClass());
+
+    private static final String NETWORK_CONFIG = "network-config";
+    private static final String TYPE = "type";
+    private static final String MTU = "mtu";
+    private static final String SEGMENT_ID = "segmentId";
+    private static final String GATEWAY_IP = "gatewayIp";
+    private static final String CIDR = "cidr";
+    private static final String HOST_ROUTES = "hostRoutes";
+    private static final String IP_POOL = "ipPool";
+    private static final String START = "start";
+    private static final String END = "end";
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    protected CoreService coreService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    protected MastershipService mastershipService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    protected ClusterService clusterService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    protected LeadershipService leadershipService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    protected KubevirtNetworkAdminService adminService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    protected KubevirtApiConfigService configService;
+
+    private final ExecutorService eventExecutor = newSingleThreadExecutor(
+            groupedThreads(this.getClass().getSimpleName(), "event-handler"));
+
+    private final InternalNetworkAttachmentDefinitionWatcher
+            watcher = new InternalNetworkAttachmentDefinitionWatcher();
+    private final InternalKubevirtApiConfigListener
+            configListener = new InternalKubevirtApiConfigListener();
+
+    CustomResourceDefinitionContext nadCrdCxt = new CustomResourceDefinitionContext
+            .Builder()
+            .withGroup("k8s.cni.cncf.io")
+            .withScope("Namespaced")
+            .withVersion("v1")
+            .withPlural("network-attachment-definitions")
+            .build();
+
+    private ApplicationId appId;
+    private NodeId localNodeId;
+
+    @Activate
+    protected void activate() {
+        appId = coreService.registerApplication(KUBEVIRT_NETWORKING_APP_ID);
+        localNodeId = clusterService.getLocalNode().id();
+        leadershipService.runForLeadership(appId.name());
+        configService.addListener(configListener);
+
+        log.info("Started");
+    }
+
+    @Deactivate
+    protected void deactivate() {
+        configService.removeListener(configListener);
+        leadershipService.withdraw(appId.name());
+        eventExecutor.shutdown();
+
+        log.info("Stopped");
+    }
+
+    private class InternalKubevirtApiConfigListener implements KubevirtApiConfigListener {
+
+        private boolean isRelevantHelper() {
+            return Objects.equals(localNodeId, leadershipService.getLeader(appId.name()));
+        }
+
+        @Override
+        public void event(KubevirtApiConfigEvent event) {
+
+            switch (event.type()) {
+                case KUBEVIRT_API_CONFIG_UPDATED:
+                    eventExecutor.execute(this::processConfigUpdate);
+                    break;
+                case KUBEVIRT_API_CONFIG_CREATED:
+                case KUBEVIRT_API_CONFIG_REMOVED:
+                default:
+                    // do nothing
+                    break;
+            }
+        }
+
+        private void processConfigUpdate() {
+            if (!isRelevantHelper()) {
+                return;
+            }
+
+            KubernetesClient client = k8sClient(configService);
+
+            if (client != null) {
+                try {
+                    client.customResource(nadCrdCxt).watch(watcher);
+                } catch (IOException e) {
+                    e.printStackTrace();
+                }
+            }
+        }
+    }
+
+    private class InternalNetworkAttachmentDefinitionWatcher
+            implements Watcher<String> {
+
+        @Override
+        public void eventReceived(Action action, String resource) {
+            switch (action) {
+                case ADDED:
+                    eventExecutor.execute(() -> processAddition(resource));
+                    break;
+                case MODIFIED:
+                    eventExecutor.execute(() -> processModification(resource));
+                    break;
+                case DELETED:
+                    eventExecutor.execute(() -> processDeletion(resource));
+                    break;
+                case ERROR:
+                    log.warn("Failures processing network-attachment-definition manipulation.");
+                    break;
+                default:
+                    break;
+            }
+        }
+
+        @Override
+        public void onClose(WatcherException e) {
+            log.warn("Network-attachment-definition watcher OnClose", e);
+        }
+
+        private void processAddition(String resource) {
+            if (!isMaster()) {
+                return;
+            }
+
+            String name = parseName(resource);
+
+            log.trace("Process NetworkAttachmentDefinition {} creating event from API server.",
+                    name);
+
+            KubevirtNetwork network = parseKubevirtNetwork(resource);
+            if (network != null) {
+                adminService.createNetwork(network);
+            }
+        }
+
+        private void processModification(String resource) {
+            if (!isMaster()) {
+                return;
+            }
+
+            String name = parseName(resource);
+
+            log.trace("Process NetworkAttachmentDefinition {} updating event from API server.",
+                    name);
+
+            KubevirtNetwork network = parseKubevirtNetwork(resource);
+            if (network != null) {
+                adminService.updateNetwork(network);
+            }
+        }
+
+        private void processDeletion(String resource) {
+            if (!isMaster()) {
+                return;
+            }
+
+            String name = parseName(resource);
+
+            log.trace("Process NetworkAttachmentDefinition {} removal event from API server.",
+                    name);
+
+            adminService.removeNetwork(name);
+        }
+
+        private boolean isMaster() {
+            return Objects.equals(localNodeId, leadershipService.getLeader(appId.name()));
+        }
+
+        private String parseName(String resource) {
+            try {
+                JSONObject json = new JSONObject(resource);
+                return json.getJSONObject("metadata").getString("name");
+            } catch (JSONException e) {
+                log.error("");
+            }
+            return "";
+        }
+
+        private KubevirtNetwork parseKubevirtNetwork(String resource) {
+            try {
+                JSONObject json = new JSONObject(resource);
+                String name = parseName(resource);
+                JSONObject annots = json.getJSONObject("metadata").getJSONObject("annotations");
+                String networkConfig = annots.getString(NETWORK_CONFIG);
+                if (networkConfig != null) {
+                    KubevirtNetwork.Builder builder = DefaultKubevirtNetwork.builder();
+
+                    JSONObject configJson = new JSONObject(networkConfig);
+                    String type = configJson.getString(TYPE);
+                    Integer mtu = configJson.getInt(MTU);
+                    String gatewayIp = configJson.getString(GATEWAY_IP);
+
+                    if (!type.equalsIgnoreCase(FLAT.name())) {
+                        builder.segmentId(configJson.getString(SEGMENT_ID));
+                    }
+
+                    String cidr = configJson.getString(CIDR);
+
+                    JSONObject poolJson = configJson.getJSONObject(IP_POOL);
+                    if (poolJson != null) {
+                        String start = poolJson.getString(START);
+                        String end = poolJson.getString(END);
+                        builder.ipPool(new KubevirtIpPool(
+                                IpAddress.valueOf(start), IpAddress.valueOf(end)));
+                    }
+
+                    builder.networkId(name).name(name).type(Type.valueOf(type))
+                            .mtu(mtu).gatewayIp(IpAddress.valueOf(gatewayIp)).cidr(cidr);
+
+                    return builder.build();
+                }
+            } catch (JSONException e) {
+                log.error("Failed to parse network attachment definition object");
+            }
+
+            return null;
+        }
+    }
+}
diff --git a/apps/kubevirt-networking/app/src/main/java/org/onosproject/kubevirtnetworking/util/KubevirtNetworkingUtil.java b/apps/kubevirt-networking/app/src/main/java/org/onosproject/kubevirtnetworking/util/KubevirtNetworkingUtil.java
index c7051bb..cef1f95 100644
--- a/apps/kubevirt-networking/app/src/main/java/org/onosproject/kubevirtnetworking/util/KubevirtNetworkingUtil.java
+++ b/apps/kubevirt-networking/app/src/main/java/org/onosproject/kubevirtnetworking/util/KubevirtNetworkingUtil.java
@@ -16,10 +16,15 @@
 package org.onosproject.kubevirtnetworking.util;
 
 import com.fasterxml.jackson.databind.ObjectMapper;
+import io.fabric8.kubernetes.client.ConfigBuilder;
+import io.fabric8.kubernetes.client.DefaultKubernetesClient;
+import io.fabric8.kubernetes.client.KubernetesClient;
 import org.apache.commons.lang.StringUtils;
 import org.apache.commons.net.util.SubnetUtils;
 import org.onlab.packet.IpAddress;
 import org.onosproject.cfg.ConfigProperty;
+import org.onosproject.kubevirtnode.api.KubevirtApiConfig;
+import org.onosproject.kubevirtnode.api.KubevirtApiConfigService;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -39,6 +44,8 @@
     private static final Logger log = LoggerFactory.getLogger(KubevirtNetworkingUtil.class);
 
     private static final int PORT_NAME_MAX_LENGTH = 15;
+    private static final String COLON_SLASH = "://";
+    private static final String COLON = ":";
 
     /**
      * Prevents object installation from external.
@@ -145,4 +152,84 @@
         SubnetUtils utils = new SubnetUtils(subnet);
         return utils.getInfo().getBroadcastAddress();
     }
+    /**
+     * Generates endpoint URL by referring to scheme, ipAddress and port.
+     *
+     * @param scheme        scheme
+     * @param ipAddress     IP address
+     * @param port          port number
+     * @return generated endpoint URL
+     */
+    public static String endpoint(KubevirtApiConfig.Scheme scheme, IpAddress ipAddress, int port) {
+        StringBuilder endpoint = new StringBuilder();
+        String protocol = org.apache.commons.lang3.StringUtils.lowerCase(scheme.name());
+
+        endpoint.append(protocol);
+        endpoint.append(COLON_SLASH);
+        endpoint.append(ipAddress.toString());
+        endpoint.append(COLON);
+        endpoint.append(port);
+
+        return endpoint.toString();
+    }
+
+    /**
+     * Generates endpoint URL by referring to scheme, ipAddress and port.
+     *
+     * @param apiConfig     kubernetes API config
+     * @return generated endpoint URL
+     */
+    public static String endpoint(KubevirtApiConfig apiConfig) {
+        return endpoint(apiConfig.scheme(), apiConfig.ipAddress(), apiConfig.port());
+    }
+
+    /**
+     * Obtains workable kubernetes client.
+     *
+     * @param config kubernetes API config
+     * @return kubernetes client
+     */
+    public static KubernetesClient k8sClient(KubevirtApiConfig config) {
+        if (config == null) {
+            log.warn("Kubernetes API server config is empty.");
+            return null;
+        }
+
+        String endpoint = endpoint(config);
+
+        ConfigBuilder configBuilder = new ConfigBuilder().withMasterUrl(endpoint);
+
+        if (config.scheme() == KubevirtApiConfig.Scheme.HTTPS) {
+            configBuilder.withTrustCerts(true)
+                    .withOauthToken(config.token())
+                    .withCaCertData(config.caCertData())
+                    .withClientCertData(config.clientCertData())
+                    .withClientKeyData(config.clientKeyData());
+        }
+
+        return new DefaultKubernetesClient(configBuilder.build());
+    }
+
+    /**
+     * Obtains workable kubernetes client.
+     *
+     * @param service kubernetes API service
+     * @return kubernetes client
+     */
+    public static KubernetesClient k8sClient(KubevirtApiConfigService service) {
+        KubevirtApiConfig config = service.apiConfig();
+        if (config == null) {
+            log.error("Failed to find valid kubernetes API configuration.");
+            return null;
+        }
+
+        KubernetesClient client = k8sClient(config);
+
+        if (client == null) {
+            log.error("Failed to connect to kubernetes API server.");
+            return null;
+        }
+
+        return client;
+    }
 }