diff --git a/runtime/app/src/test/java/org/onosproject/yang/runtime/app/DefaultYangModelRegistryTest.java b/runtime/app/src/test/java/org/onosproject/yang/runtime/app/DefaultYangModelRegistryTest.java
new file mode 100644
index 0000000..8445d34
--- /dev/null
+++ b/runtime/app/src/test/java/org/onosproject/yang/runtime/app/DefaultYangModelRegistryTest.java
@@ -0,0 +1,400 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * 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.yang.runtime.app;
+
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.ExpectedException;
+import org.onosproject.yang.compiler.datamodel.YangNode;
+import org.onosproject.yang.compiler.datamodel.YangRevision;
+import org.onosproject.yang.compiler.datamodel.YangSchemaNode;
+
+import java.io.IOException;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.core.Is.is;
+import static org.onosproject.yang.compiler.plugin.utils.YangApacheUtils.getDateInStringFormat;
+
+/**
+ * Unit test for model registry.
+ */
+public class DefaultYangModelRegistryTest {
+
+    private static final String SERVICE_NAME_3 =
+            "org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf" +
+                    ".network3.rev20151208.IetfNetwork3Service";
+    private static final String SCHEMA_NAME_3 = "ietf-network3";
+    private static final String INTERFACE_NAME_3 =
+            "org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf" +
+                    ".network3.rev20151208.IetfNetwork3";
+    private static final String OP_PARAM_NAME_3 =
+            "org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf" +
+                    ".network3.rev20151208.IetfNetwork3OpParam";
+
+    private static final String SCHEMA_NAME_4_14 = "ietf-network4@2014-00-08";
+    private static final String SCHEMA_NAME_4_15 = "ietf-network4@2015-00-08";
+    private static final String SCHEMA_NAME_4_16 = "ietf-network4@2016-00-08";
+    private static final String SCHEMA_NAME_4_17 = "ietf-network4@2017-00-08";
+    private static final String SCHEMA_NAME_4 = "ietf-network4";
+    private static final String SERVICE_NAME_REV_14 =
+            "org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf" +
+                    ".network4.rev20141208.IetfNetwork4Service";
+    private static final String INTERFACE_NAME_REV_14 =
+            "org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf" +
+                    ".network4.rev20141208.IetfNetwork4";
+    private static final String OP_PARAM_NAME_REV_14 =
+            "org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf" +
+                    ".network4.rev20141208.IetfNetwork4OpParam";
+
+    private static final String SERVICE_NAME_REV_15 =
+            "org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf" +
+                    ".network4.rev20151208.IetfNetwork4Service";
+    private static final String INTERFACE_NAME_REV_15 =
+            "org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf" +
+                    ".network4.rev20151208.IetfNetwork4";
+    private static final String OP_PARAM_NAME_REV_15 =
+            "org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf" +
+                    ".network4.rev20151208.IetfNetwork4OpParam";
+
+    private static final String SERVICE_NAME_REV_16 =
+            "org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf" +
+                    ".network4.rev20161208.IetfNetwork4Service";
+    private static final String INTERFACE_NAME_REV_16 =
+            "org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf" +
+                    ".network4.rev20161208.IetfNetwork4";
+    private static final String OP_PARAM_NAME_REV_16 =
+            "org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf" +
+                    ".network4.rev20161208.IetfNetwork4OpParam";
+
+    private static final String SERVICE_NAME_REV_17 =
+            "org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf" +
+                    ".network4.rev20171208.IetfNetwork4Service";
+    private static final String INTERFACE_NAME_REV_17 =
+            "org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf" +
+                    ".network4.rev20171208.IetfNetwork4";
+    private static final String OP_PARAM_NAME_REV_17 =
+            "org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf" +
+                    ".network4.rev20171208.IetfNetwork4OpParam";
+
+    private static final String SERVICE_NAME_NO_REV =
+            "org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf" +
+                    ".network4.IetfNetwork4Service";
+    private static final String INTERFACE_NAME_NO_REV =
+            "org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf" +
+                    ".network4.IetfNetwork4";
+    private static final String OP_PARAM_NAME_NO_REV =
+            "org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf" +
+                    ".network4.IetfNetwork4OpParam";
+
+    private static final String UN_REG_SCHEMA_NAME = "ietf-routing";
+    private static final String UN_REG_INTERFACE_NAME = "IetfRouting";
+    private static final String UN_REG_OP_PARAM_NAME = "IetfRoutingOpParam";
+    private static final String UN_REG_SERVICE_NAME = "IetfRoutingService";
+    private static final String CHECK = "check";
+    private static final String DATE_NAMESPACE = "2015-00-08";
+    private static final String NAMESPACE =
+            "urn:ietf:params:xml:ns:yang:ietf-network4:check:namespace";
+
+    private final TestYangSchemaNodeProvider provider =
+            new TestYangSchemaNodeProvider();
+    @Rule
+    public ExpectedException thrown = ExpectedException.none();
+
+    /**
+     * Unit test case in which schema node should be present.
+     *
+     * @throws IOException when fails to do IO operation
+     */
+    @Test
+    public void testForGetSchemaNode()
+            throws IOException {
+
+        provider.processSchemaRegistry();
+
+        DefaultYangModelRegistry registry = provider.registry();
+
+        YangSchemaNode yangNode = registry.getForSchemaName(SCHEMA_NAME_3);
+        assertThat(true, is(SCHEMA_NAME_3.equals(yangNode.getName())));
+
+        yangNode =
+                registry.getForInterfaceFileName(
+                        INTERFACE_NAME_3);
+        assertThat(true, is(SCHEMA_NAME_3.equals(yangNode.getName())));
+
+        yangNode =
+                registry.getForOpPramFileName(
+                        OP_PARAM_NAME_3);
+        assertThat(true, is(SCHEMA_NAME_3.equals(yangNode.getName())));
+
+//        provider.unregisterService(SERVICE_NAME_3);
+        //TODO: fix unregister UT.
+//
+//        yangNode = registry.getForAppName(SERVICE_NAME_3);
+//        assertThat(true, is(yangNode == null));
+//
+//        yangNode = registry.getForSchemaName(SCHEMA_NAME_3);
+//        assertThat(true, is(yangNode == null));
+//
+//        yangNode =
+//                registry.getForInterfaceFileName(
+//                        INTERFACE_NAME_3);
+//        assertThat(true, is(yangNode == null));
+//
+//        yangNode =
+//                registry.getForOpPramFileName(
+//                        OP_PARAM_NAME_3);
+//        assertThat(true, is(yangNode == null));
+    }
+
+    /**
+     * Unit test case in which schema node should be present with multi
+     * revisions.
+     *
+     * @throws IOException when fails to do IO operation
+     */
+    @Test
+    public void testForGetSchemaNodeWhenNoRevision()
+            throws IOException {
+
+        provider.processSchemaRegistry();
+        DefaultYangModelRegistry registry =
+                provider.registry();
+
+        //Service with rev.
+        YangSchemaNode yangNode = registry.getForSchemaName(SCHEMA_NAME_4_15);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        yangNode =
+                registry.getForInterfaceFileName(
+                        INTERFACE_NAME_REV_15);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        yangNode =
+                registry.getForOpPramFileName(
+                        OP_PARAM_NAME_REV_15);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        //       provider.unregisterService(SERVICE_NAME_REV_15);
+
+        yangNode = registry.getForAppName(SERVICE_NAME_REV_15);
+        assertThat(true, is(yangNode == null));
+
+        //Here the yangNode should be the node which does not have revision.
+        
+        // asset should pass with false.
+        yangNode = registry.getForSchemaName(SCHEMA_NAME_4);
+        assertThat(true, is(((YangNode) yangNode).getRevision() == null));
+
+        yangNode = registry.getForSchemaName(SCHEMA_NAME_4);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        yangNode =
+                registry.getForInterfaceFileName(
+                        INTERFACE_NAME_NO_REV);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        yangNode =
+                registry.getForOpPramFileName(
+                        OP_PARAM_NAME_NO_REV);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        //provider.unregisterService(SERVICE_NAME_NO_REV);
+
+        yangNode = registry.getForAppName(SERVICE_NAME_NO_REV);
+        assertThat(true, is(yangNode == null));
+
+        //Here the yangNode should be the node which have different revision.
+        yangNode = registry.getForSchemaName(SCHEMA_NAME_4);
+        assertThat(true, is(yangNode != null));
+        //TODO: ureg.
+//        assertThat(true, is(((YangNode) yangNode).getRevision() != null));
+    }
+
+    /**
+     * Unit test case in which schema node should be present with multi
+     * revisions.
+     *
+     * @throws IOException when fails to do IO operation
+     */
+    //TODO: add unreg in UT
+    public void testForGetSchemaNodeWhenMultiRevision()
+            throws IOException {
+
+        provider.processSchemaRegistry();
+        DefaultYangModelRegistry registry =
+                provider.registry();
+
+        //Service with rev.
+        YangSchemaNode yangNode = registry.getForSchemaName(SCHEMA_NAME_4_15);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        yangNode =
+                registry.getForInterfaceFileName(
+                        INTERFACE_NAME_REV_15);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        yangNode =
+                registry.getForOpPramFileName(
+                        OP_PARAM_NAME_REV_15);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        //As we have not registered an  application this object should be null.
+        Object object = registry.getRegisteredClass(yangNode);
+        assertThat(true, is(object == null));
+//        provider.unregisterService(SERVICE_NAME_REV_15);
+
+        yangNode = registry.getForAppName(SERVICE_NAME_REV_15);
+        assertThat(true, is(yangNode == null));
+
+        //Here the yangNode should be the node which does not have revision.
+        // asset should pass with false.
+        yangNode = registry.getForSchemaName(SCHEMA_NAME_4);
+        assertThat(true, is(((YangNode) yangNode).getRevision() == null));
+
+        //Service with different revision.
+        yangNode = registry
+                .getForAppName(SERVICE_NAME_REV_16);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        yangNode = registry.getForSchemaName(SCHEMA_NAME_4_16);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        yangNode =
+                registry.getForInterfaceFileName(
+                        INTERFACE_NAME_REV_16);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        yangNode =
+                registry.getForOpPramFileName(
+                        OP_PARAM_NAME_REV_16);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        //As we have not registered an  application this object should be null.
+        object = registry.getRegisteredClass(yangNode);
+        assertThat(true, is(object == null));
+//        provider.unregisterService(SERVICE_NAME_REV_16);
+
+        yangNode = registry.getForAppName(SERVICE_NAME_REV_16);
+        assertThat(true, is(yangNode == null));
+
+        //Here the yangNode should be the node which have different revision.
+        yangNode = registry.getForSchemaName(SCHEMA_NAME_4);
+        assertThat(true, is(((YangNode) yangNode).getRevision() == null));
+
+        //Service with different revision.
+        yangNode = registry.getForAppName(SERVICE_NAME_REV_17);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        yangNode = registry.getForSchemaName(SCHEMA_NAME_4_17);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        yangNode =
+                registry.getForInterfaceFileName(
+                        INTERFACE_NAME_REV_17);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        yangNode =
+                registry.getForOpPramFileName(
+                        OP_PARAM_NAME_REV_17);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        //As we have not registered an  application this object should be null.
+        object = registry.getRegisteredClass(yangNode);
+        assertThat(true, is(object == null));
+//        provider.unregisterService(SERVICE_NAME_REV_17);
+
+        yangNode = registry.getForAppName(SERVICE_NAME_REV_17);
+        assertThat(true, is(yangNode == null));
+
+        //Here the yangNode should be the node which have different revision.
+        yangNode = registry.getForSchemaName(SCHEMA_NAME_4);
+        assertThat(true, is(((YangNode) yangNode).getRevision() == null));
+
+        //Service no revision.
+        yangNode = registry.getForAppName(SERVICE_NAME_NO_REV);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        yangNode = registry.getForSchemaName(SCHEMA_NAME_4);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        yangNode =
+                registry.getForInterfaceFileName(
+                        INTERFACE_NAME_NO_REV);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        yangNode =
+                registry.getForOpPramFileName(
+                        OP_PARAM_NAME_NO_REV);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        //As we have not registered an  application this object should be null.
+        object = registry.getRegisteredClass(yangNode);
+        assertThat(true, is(object == null));
+        //       provider.unregisterService(SERVICE_NAME_NO_REV);
+
+        yangNode = registry.getForAppName(SERVICE_NAME_NO_REV);
+        assertThat(true, is(yangNode == null));
+
+        //Here the yangNode should be the node which have different revision.
+        yangNode = registry.getForSchemaName(SCHEMA_NAME_4);
+        assertThat(true, is(yangNode != null));
+        assertThat(true, is(((YangNode) yangNode).getRevision() != null));
+
+        //Service with different revision.
+        yangNode = registry.getForAppName(SERVICE_NAME_REV_14);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        yangNode = registry.getForSchemaName(SCHEMA_NAME_4_14);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        yangNode =
+                registry.getForInterfaceFileName(
+                        INTERFACE_NAME_REV_14);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        yangNode =
+                registry.getForOpPramFileName(
+                        OP_PARAM_NAME_REV_14);
+        assertThat(true, is(SCHEMA_NAME_4.equals(yangNode.getName())));
+
+        //As we have not registered an  application this object should be null.
+        object = registry.getRegisteredClass(yangNode);
+        assertThat(true, is(object == null));
+//        provider.unregisterService(SERVICE_NAME_REV_14);
+
+        yangNode = registry.getForAppName(SERVICE_NAME_REV_14);
+        assertThat(true, is(yangNode == null));
+    }
+
+    /**
+     * get schema for namespace in decode test.
+     */
+    @Test
+    public void testGetNodeWrtNamespace() {
+        provider.processSchemaRegistry();
+        DefaultYangModelRegistry registry = provider.registry();
+
+        YangSchemaNode yangNode = registry.getForNameSpace(NAMESPACE);
+        assertThat(true, is(CHECK.equals(yangNode.getName())));
+
+        YangRevision rev = ((YangNode) yangNode).getRevision();
+        assertThat(true, is(rev != null));
+
+        String date = getDateInStringFormat((YangNode) yangNode);
+        assertThat(true, is(DATE_NAMESPACE.equals(date)));
+    }
+}
diff --git a/runtime/app/src/test/java/org/onosproject/yang/runtime/app/TestYangSchemaNodeProvider.java b/runtime/app/src/test/java/org/onosproject/yang/runtime/app/TestYangSchemaNodeProvider.java
new file mode 100644
index 0000000..a42f2fb
--- /dev/null
+++ b/runtime/app/src/test/java/org/onosproject/yang/runtime/app/TestYangSchemaNodeProvider.java
@@ -0,0 +1,113 @@
+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * 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.yang.runtime.app;
+
+import org.onosproject.yang.YangModel;
+import org.onosproject.yang.compiler.datamodel.YangNode;
+import org.onosproject.yang.compiler.datamodel.YangSchemaNode;
+import org.onosproject.yang.runtime.api.AppModuleInfo;
+import org.onosproject.yang.runtime.api.ModelRegistrationParam;
+import org.onosproject.yang.runtime.api.YangModelRegistry;
+
+import java.io.File;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Set;
+
+import static org.onosproject.yang.compiler.datamodel.utils.DataModelUtils.deSerializeDataModel;
+import static org.onosproject.yang.compiler.plugin.utils.YangApacheUtils.processModuleId;
+import static org.onosproject.yang.compiler.plugin.utils.YangApacheUtils.processYangModel;
+import static org.onosproject.yang.compiler.utils.UtilConstants.TEMP;
+import static org.onosproject.yang.compiler.utils.io.impl.YangIoUtils.deleteDirectory;
+import static org.onosproject.yang.runtime.utils.RuntimeHelper.getInterfaceClassName;
+
+/**
+ * Represents mock bundle context. provides bundle context for YSR to do unit
+ * testing.
+ * //TODO: add unreg ut.
+ */
+public class TestYangSchemaNodeProvider {
+
+    private static final String FS = File.separator;
+    private static final String PATH = System.getProperty("user.dir") +
+            FS + "target" + FS + "classes" + FS;
+    private static final String SER_FILE_PATH = "yang" + FS + "resources" +
+            FS + "YangMetaData.ser";
+    private static final String META_PATH = PATH + SER_FILE_PATH;
+    private static final String TEMP_FOLDER_PATH = PATH + TEMP;
+    private YangModelRegistry reg = new DefaultYangModelRegistry();
+    private List<YangNode> nodes = new ArrayList<>();
+
+    /**
+     * Creates an instance of mock bundle context.
+     */
+    public TestYangSchemaNodeProvider() {
+    }
+
+    /**
+     * Process YANG schema node for a application.
+     */
+    public void processSchemaRegistry() {
+        try {
+            //Need to deserialize generated meta data file for unit tests.
+            Set<YangNode> appNode = deSerializeDataModel(META_PATH);
+            nodes.addAll(appNode);
+
+            //Process loading class file.
+            String appName;
+            ClassLoader classLoader = TestYangSchemaNodeProvider.class.getClassLoader();
+            for (YangSchemaNode node : nodes) {
+
+                //If service class is not generated then use
+                // interface file to load this class.
+                appName = getInterfaceClassName(node);
+                Class<?> cls;
+                try {
+                    cls = classLoader.loadClass(appName);
+                } catch (ClassNotFoundException e) {
+                    continue;
+                }
+
+                //Create model registration param.
+                ModelRegistrationParam param = new
+                        DefaultModelRegistrationParam();
+
+                //create a new YANG model
+                YangModel model = processYangModel(META_PATH, nodes);
+                //set YANG model
+                param.setYangModel(model);
+                //generate app info.
+                AppModuleInfo info = new DefaultAppModuleInfo();
+                info.setModuleClass(cls);
+                param.addAppModuleInfo(processModuleId((YangNode) node), info);
+                reg.registerModel(param);
+            }
+            deleteDirectory(TEMP_FOLDER_PATH);
+        } catch (IOException e) {
+        }
+    }
+
+    /**
+     * Returns schema registry.
+     *
+     * @return schema registry
+     */
+    public DefaultYangModelRegistry registry() {
+        return (DefaultYangModelRegistry) reg;
+    }
+}
diff --git a/runtime/app/src/test/resources/ysrTestYangFiles/CheckWithNamespace.yang b/runtime/app/src/test/resources/ysrTestYangFiles/CheckWithNamespace.yang
new file mode 100644
index 0000000..7e5726e
--- /dev/null
+++ b/runtime/app/src/test/resources/ysrTestYangFiles/CheckWithNamespace.yang
@@ -0,0 +1,80 @@
+   module check {
+     yang-version 1;
+     namespace "urn:ietf:params:xml:ns:yang:ietf-network4:check:namespace";
+     prefix nd;
+
+     organization
+       "IETF I2RS (Interface to the Routing System) Working Group";
+
+     contact
+       "WG Web:    <http://tools.ietf.org/wg/i2rs/>
+        WG List:   <mailto:i2rs@ietf.org>
+
+        WG Chair:  Susan Hares
+                   <mailto:shares@ndzh.com>
+
+        WG Chair:  Jeffrey Haas
+                   <mailto:jhaas@pfrc.org>
+
+        Editor:    Alexander Clemm
+                   <mailto:alex@cisco.com>
+
+        Editor:    Jan Medved
+                   <mailto:jmedved@cisco.com>
+
+        Editor:    Robert Varga
+                   <mailto:rovarga@cisco.com>
+
+        Editor:    Tony Tkacik
+                   <mailto:ttkacik@cisco.com>
+
+        Editor:    Nitin Bahadur
+                   <mailto:nitin_bahadur@yahoo.com>
+
+        Editor:    Hariharan Ananthakrishnan
+                   <mailto:hari@packetdesign.com>";
+
+     description
+       "This module defines a common base model for a collection
+        of nodes in a network. Node definitions are further used
+        in network topologies and inventories.
+
+        Copyright (c) 2015 IETF Trust and the persons identified as
+        authors of the code.  All rights reserved.
+
+        Redistribution and use in source and binary forms, with or
+        without modification, is permitted pursuant to, and subject
+        to the license terms contained in, the Simplified BSD License
+        set forth in Section 4.c of the IETF Trust's Legal Provisions
+        Relating to IETF Documents
+        (http://trustee.ietf.org/license-info).
+
+        This version of this YANG module is part of
+        draft-ietf-i2rs-yang-network-topo-02;
+        see the RFC itself for full legal notices.
+
+        NOTE TO RFC EDITOR: Please replace above reference to
+        draft-ietf-i2rs-yang-network-topo-02 with RFC
+        number when published (i.e. RFC xxxx).";
+
+     revision 2015-12-08 {
+       description
+         "Initial revision.
+          NOTE TO RFC EDITOR: Please replace the following reference
+          to draft-ietf-i2rs-yang-network-topo-02 with
+          RFC number when published (i.e. RFC xxxx).";
+       reference
+         "draft-ietf-i2rs-yang-network-topo-02";
+     }
+
+         container networks {
+             leaf id {
+                 type int32;
+             }
+             container network {
+                  leaf ip-address {
+                      type int32;
+                  }
+             }
+         }
+}
diff --git a/runtime/app/src/test/resources/ysrTestYangFiles/multiRevisions/norev.yang b/runtime/app/src/test/resources/ysrTestYangFiles/multiRevisions/norev.yang
new file mode 100644
index 0000000..a537824
--- /dev/null
+++ b/runtime/app/src/test/resources/ysrTestYangFiles/multiRevisions/norev.yang
@@ -0,0 +1,71 @@
+   module ietf-network4 {
+     yang-version 1;
+     namespace "urn:ietf:params:xml:ns:yang:ietf-network4";
+     prefix nd;
+
+     organization
+       "IETF I2RS (Interface to the Routing System) Working Group";
+
+     contact
+       "WG Web:    <http://tools.ietf.org/wg/i2rs/>
+        WG List:   <mailto:i2rs@ietf.org>
+
+        WG Chair:  Susan Hares
+                   <mailto:shares@ndzh.com>
+
+        WG Chair:  Jeffrey Haas
+                   <mailto:jhaas@pfrc.org>
+
+        Editor:    Alexander Clemm
+                   <mailto:alex@cisco.com>
+
+        Editor:    Jan Medved
+                   <mailto:jmedved@cisco.com>
+
+        Editor:    Robert Varga
+                   <mailto:rovarga@cisco.com>
+
+        Editor:    Tony Tkacik
+                   <mailto:ttkacik@cisco.com>
+
+        Editor:    Nitin Bahadur
+                   <mailto:nitin_bahadur@yahoo.com>
+
+        Editor:    Hariharan Ananthakrishnan
+                   <mailto:hari@packetdesign.com>";
+
+     description
+       "This module defines a common base model for a collection
+        of nodes in a network. Node definitions are further used
+        in network topologies and inventories.
+
+        Copyright (c) 2015 IETF Trust and the persons identified as
+        authors of the code.  All rights reserved.
+
+        Redistribution and use in source and binary forms, with or
+        without modification, is permitted pursuant to, and subject
+        to the license terms contained in, the Simplified BSD License
+        set forth in Section 4.c of the IETF Trust's Legal Provisions
+        Relating to IETF Documents
+        (http://trustee.ietf.org/license-info).
+
+        This version of this YANG module is part of
+        draft-ietf-i2rs-yang-network-topo-02;
+        see the RFC itself for full legal notices.
+
+        NOTE TO RFC EDITOR: Please replace above reference to
+        draft-ietf-i2rs-yang-network-topo-02 with RFC
+        number when published (i.e. RFC xxxx).";
+
+         container networks {
+             leaf id {
+                 type int32;
+             }
+             container network {
+                  leaf ip-address {
+                      type int32;
+                  }
+             }
+         }
+
+}
diff --git a/runtime/app/src/test/resources/ysrTestYangFiles/multiRevisions/withrev.yang b/runtime/app/src/test/resources/ysrTestYangFiles/multiRevisions/withrev.yang
new file mode 100644
index 0000000..b181f36
--- /dev/null
+++ b/runtime/app/src/test/resources/ysrTestYangFiles/multiRevisions/withrev.yang
@@ -0,0 +1,81 @@
+   module ietf-network4 {
+     yang-version 1;
+     namespace "urn:ietf:params:xml:ns:yang:ietf-network4";
+     prefix nd;
+
+     organization
+       "IETF I2RS (Interface to the Routing System) Working Group";
+
+     contact
+       "WG Web:    <http://tools.ietf.org/wg/i2rs/>
+        WG List:   <mailto:i2rs@ietf.org>
+
+        WG Chair:  Susan Hares
+                   <mailto:shares@ndzh.com>
+
+        WG Chair:  Jeffrey Haas
+                   <mailto:jhaas@pfrc.org>
+
+        Editor:    Alexander Clemm
+                   <mailto:alex@cisco.com>
+
+        Editor:    Jan Medved
+                   <mailto:jmedved@cisco.com>
+
+        Editor:    Robert Varga
+                   <mailto:rovarga@cisco.com>
+
+        Editor:    Tony Tkacik
+                   <mailto:ttkacik@cisco.com>
+
+        Editor:    Nitin Bahadur
+                   <mailto:nitin_bahadur@yahoo.com>
+
+        Editor:    Hariharan Ananthakrishnan
+                   <mailto:hari@packetdesign.com>";
+
+     description
+       "This module defines a common base model for a collection
+        of nodes in a network. Node definitions are further used
+        in network topologies and inventories.
+
+        Copyright (c) 2015 IETF Trust and the persons identified as
+        authors of the code.  All rights reserved.
+
+        Redistribution and use in source and binary forms, with or
+        without modification, is permitted pursuant to, and subject
+        to the license terms contained in, the Simplified BSD License
+        set forth in Section 4.c of the IETF Trust's Legal Provisions
+        Relating to IETF Documents
+        (http://trustee.ietf.org/license-info).
+
+        This version of this YANG module is part of
+        draft-ietf-i2rs-yang-network-topo-02;
+        see the RFC itself for full legal notices.
+
+        NOTE TO RFC EDITOR: Please replace above reference to
+        draft-ietf-i2rs-yang-network-topo-02 with RFC
+        number when published (i.e. RFC xxxx).";
+
+     revision 2015-12-08 {
+       description
+         "Initial revision.
+          NOTE TO RFC EDITOR: Please replace the following reference
+          to draft-ietf-i2rs-yang-network-topo-02 with
+          RFC number when published (i.e. RFC xxxx).";
+       reference
+         "draft-ietf-i2rs-yang-network-topo-02";
+     }
+
+         container networks {
+             leaf id {
+                 type int32;
+             }
+             container network {
+                  leaf ip-address {
+                      type int32;
+                  }
+             }
+         }
+
+}
diff --git a/runtime/app/src/test/resources/ysrTestYangFiles/multiRevisions/withrev2.yang b/runtime/app/src/test/resources/ysrTestYangFiles/multiRevisions/withrev2.yang
new file mode 100644
index 0000000..29d5485
--- /dev/null
+++ b/runtime/app/src/test/resources/ysrTestYangFiles/multiRevisions/withrev2.yang
@@ -0,0 +1,80 @@
+   module ietf-network4 {
+     yang-version 1;
+     namespace "urn:ietf:params:xml:ns:yang:ietf-network4";
+     prefix nd;
+
+     organization
+       "IETF I2RS (Interface to the Routing System) Working Group";
+
+     contact
+       "WG Web:    <http://tools.ietf.org/wg/i2rs/>
+        WG List:   <mailto:i2rs@ietf.org>
+
+        WG Chair:  Susan Hares
+                   <mailto:shares@ndzh.com>
+
+        WG Chair:  Jeffrey Haas
+                   <mailto:jhaas@pfrc.org>
+
+        Editor:    Alexander Clemm
+                   <mailto:alex@cisco.com>
+
+        Editor:    Jan Medved
+                   <mailto:jmedved@cisco.com>
+
+        Editor:    Robert Varga
+                   <mailto:rovarga@cisco.com>
+
+        Editor:    Tony Tkacik
+                   <mailto:ttkacik@cisco.com>
+
+        Editor:    Nitin Bahadur
+                   <mailto:nitin_bahadur@yahoo.com>
+
+        Editor:    Hariharan Ananthakrishnan
+                   <mailto:hari@packetdesign.com>";
+
+     description
+       "This module defines a common base model for a collection
+        of nodes in a network. Node definitions are further used
+        in network topologies and inventories.
+
+        Copyright (c) 2015 IETF Trust and the persons identified as
+        authors of the code.  All rights reserved.
+
+        Redistribution and use in source and binary forms, with or
+        without modification, is permitted pursuant to, and subject
+        to the license terms contained in, the Simplified BSD License
+        set forth in Section 4.c of the IETF Trust's Legal Provisions
+        Relating to IETF Documents
+        (http://trustee.ietf.org/license-info).
+
+        This version of this YANG module is part of
+        draft-ietf-i2rs-yang-network-topo-02;
+        see the RFC itself for full legal notices.
+
+        NOTE TO RFC EDITOR: Please replace above reference to
+        draft-ietf-i2rs-yang-network-topo-02 with RFC
+        number when published (i.e. RFC xxxx).";
+
+     revision 2016-12-08 {
+       description
+         "Initial revision.
+          NOTE TO RFC EDITOR: Please replace the following reference
+          to draft-ietf-i2rs-yang-network-topo-02 with
+          RFC number when published (i.e. RFC xxxx).";
+       reference
+         "draft-ietf-i2rs-yang-network-topo-02";
+     }
+
+         container networks {
+             leaf id {
+                 type int32;
+             }
+             container network {
+                  leaf ip-address {
+                      type int32;
+                  }
+             }
+         }
+}
diff --git a/runtime/app/src/test/resources/ysrTestYangFiles/multiRevisions/withrev3.yang b/runtime/app/src/test/resources/ysrTestYangFiles/multiRevisions/withrev3.yang
new file mode 100644
index 0000000..c8a2a0a
--- /dev/null
+++ b/runtime/app/src/test/resources/ysrTestYangFiles/multiRevisions/withrev3.yang
@@ -0,0 +1,81 @@
+   module ietf-network4 {
+     yang-version 1;
+     namespace "urn:ietf:params:xml:ns:yang:ietf-network4";
+     prefix nd;
+
+     organization
+       "IETF I2RS (Interface to the Routing System) Working Group";
+
+     contact
+       "WG Web:    <http://tools.ietf.org/wg/i2rs/>
+        WG List:   <mailto:i2rs@ietf.org>
+
+        WG Chair:  Susan Hares
+                   <mailto:shares@ndzh.com>
+
+        WG Chair:  Jeffrey Haas
+                   <mailto:jhaas@pfrc.org>
+
+        Editor:    Alexander Clemm
+                   <mailto:alex@cisco.com>
+
+        Editor:    Jan Medved
+                   <mailto:jmedved@cisco.com>
+
+        Editor:    Robert Varga
+                   <mailto:rovarga@cisco.com>
+
+        Editor:    Tony Tkacik
+                   <mailto:ttkacik@cisco.com>
+
+        Editor:    Nitin Bahadur
+                   <mailto:nitin_bahadur@yahoo.com>
+
+        Editor:    Hariharan Ananthakrishnan
+                   <mailto:hari@packetdesign.com>";
+
+     description
+       "This module defines a common base model for a collection
+        of nodes in a network. Node definitions are further used
+        in network topologies and inventories.
+
+        Copyright (c) 2015 IETF Trust and the persons identified as
+        authors of the code.  All rights reserved.
+
+        Redistribution and use in source and binary forms, with or
+        without modification, is permitted pursuant to, and subject
+        to the license terms contained in, the Simplified BSD License
+        set forth in Section 4.c of the IETF Trust's Legal Provisions
+        Relating to IETF Documents
+        (http://trustee.ietf.org/license-info).
+
+        This version of this YANG module is part of
+        draft-ietf-i2rs-yang-network-topo-02;
+        see the RFC itself for full legal notices.
+
+        NOTE TO RFC EDITOR: Please replace above reference to
+        draft-ietf-i2rs-yang-network-topo-02 with RFC
+        number when published (i.e. RFC xxxx).";
+
+     revision 2014-12-08 {
+       description
+         "Initial revision.
+          NOTE TO RFC EDITOR: Please replace the following reference
+          to draft-ietf-i2rs-yang-network-topo-02 with
+          RFC number when published (i.e. RFC xxxx).";
+       reference
+         "draft-ietf-i2rs-yang-network-topo-02";
+     }
+
+         container networks {
+             leaf id {
+                 type int32;
+             }
+             container network {
+                  leaf ip-address {
+                      type int32;
+                  }
+             }
+         }
+
+}
diff --git a/runtime/app/src/test/resources/ysrTestYangFiles/multiRevisions/withrev4.yang b/runtime/app/src/test/resources/ysrTestYangFiles/multiRevisions/withrev4.yang
new file mode 100644
index 0000000..9352fb4
--- /dev/null
+++ b/runtime/app/src/test/resources/ysrTestYangFiles/multiRevisions/withrev4.yang
@@ -0,0 +1,76 @@
+   module ietf-network4 {
+     yang-version 1;
+     namespace "urn:ietf:params:xml:ns:yang:ietf-network4";
+     prefix nd;
+
+     organization
+       "IETF I2RS (Interface to the Routing System) Working Group";
+
+     contact
+       "WG Web:    <http://tools.ietf.org/wg/i2rs/>
+        WG List:   <mailto:i2rs@ietf.org>
+
+        WG Chair:  Susan Hares
+                   <mailto:shares@ndzh.com>
+
+        WG Chair:  Jeffrey Haas
+                   <mailto:jhaas@pfrc.org>
+
+        Editor:    Alexander Clemm
+                   <mailto:alex@cisco.com>
+
+        Editor:    Jan Medved
+                   <mailto:jmedved@cisco.com>
+
+        Editor:    Robert Varga
+                   <mailto:rovarga@cisco.com>
+
+        Editor:    Tony Tkacik
+                   <mailto:ttkacik@cisco.com>
+
+        Editor:    Nitin Bahadur
+                   <mailto:nitin_bahadur@yahoo.com>
+
+        Editor:    Hariharan Ananthakrishnan
+                   <mailto:hari@packetdesign.com>";
+
+     description
+       "This module defines a common base model for a collection
+        of nodes in a network. Node definitions are further used
+        in network topologies and inventories.
+
+        Copyright (c) 2015 IETF Trust and the persons identified as
+        authors of the code.  All rights reserved.
+
+        Redistribution and use in source and binary forms, with or
+        without modification, is permitted pursuant to, and subject
+        to the license terms contained in, the Simplified BSD License
+        set forth in Section 4.c of the IETF Trust's Legal Provisions
+        Relating to IETF Documents
+        (http://trustee.ietf.org/license-info).
+
+        This version of this YANG module is part of
+        draft-ietf-i2rs-yang-network-topo-02;
+        see the RFC itself for full legal notices.
+
+        NOTE TO RFC EDITOR: Please replace above reference to
+        draft-ietf-i2rs-yang-network-topo-02 with RFC
+        number when published (i.e. RFC xxxx).";
+
+     revision 2017-12-08 {
+       description
+         "Initial revision.
+          NOTE TO RFC EDITOR: Please replace the following reference
+          to draft-ietf-i2rs-yang-network-topo-02 with
+          RFC number when published (i.e. RFC xxxx).";
+       reference
+         "draft-ietf-i2rs-yang-network-topo-02";
+     }
+
+     container network {
+          leaf ip {
+             type int32;
+          }
+     }
+
+}
diff --git a/runtime/app/src/test/resources/ysrTestYangFiles/withoutNotification/ysr3.yang b/runtime/app/src/test/resources/ysrTestYangFiles/withoutNotification/ysr3.yang
new file mode 100644
index 0000000..0e86062
--- /dev/null
+++ b/runtime/app/src/test/resources/ysrTestYangFiles/withoutNotification/ysr3.yang
@@ -0,0 +1,81 @@
+   module ietf-network3 {
+     yang-version 1;
+     namespace "urn:ietf:params:xml:ns:yang:ietf-network3";
+     prefix nd;
+
+     organization
+       "IETF I2RS (Interface to the Routing System) Working Group";
+
+     contact
+       "WG Web:    <http://tools.ietf.org/wg/i2rs/>
+        WG List:   <mailto:i2rs@ietf.org>
+
+        WG Chair:  Susan Hares
+                   <mailto:shares@ndzh.com>
+
+        WG Chair:  Jeffrey Haas
+                   <mailto:jhaas@pfrc.org>
+
+        Editor:    Alexander Clemm
+                   <mailto:alex@cisco.com>
+
+        Editor:    Jan Medved
+                   <mailto:jmedved@cisco.com>
+
+        Editor:    Robert Varga
+                   <mailto:rovarga@cisco.com>
+
+        Editor:    Tony Tkacik
+                   <mailto:ttkacik@cisco.com>
+
+        Editor:    Nitin Bahadur
+                   <mailto:nitin_bahadur@yahoo.com>
+
+        Editor:    Hariharan Ananthakrishnan
+                   <mailto:hari@packetdesign.com>";
+
+     description
+       "This module defines a common base model for a collection
+        of nodes in a network. Node definitions are further used
+        in network topologies and inventories.
+
+        Copyright (c) 2015 IETF Trust and the persons identified as
+        authors of the code.  All rights reserved.
+
+        Redistribution and use in source and binary forms, with or
+        without modification, is permitted pursuant to, and subject
+        to the license terms contained in, the Simplified BSD License
+        set forth in Section 4.c of the IETF Trust's Legal Provisions
+        Relating to IETF Documents
+        (http://trustee.ietf.org/license-info).
+
+        This version of this YANG module is part of
+        draft-ietf-i2rs-yang-network-topo-02;
+        see the RFC itself for full legal notices.
+
+        NOTE TO RFC EDITOR: Please replace above reference to
+        draft-ietf-i2rs-yang-network-topo-02 with RFC
+        number when published (i.e. RFC xxxx).";
+
+     revision 2015-12-08 {
+       description
+         "Initial revision.
+          NOTE TO RFC EDITOR: Please replace the following reference
+          to draft-ietf-i2rs-yang-network-topo-02 with
+          RFC number when published (i.e. RFC xxxx).";
+       reference
+         "draft-ietf-i2rs-yang-network-topo-02";
+     }
+
+     container networks {
+         leaf id {
+            type int32;
+         }
+         container network {
+              leaf ip-address {
+                  type int32;
+              }
+         }
+     }
+
+}