diff --git a/apps/restconf/api/src/main/java/org/onosproject/restconf/api/Patch.java b/apps/restconf/api/src/main/java/org/onosproject/restconf/api/Patch.java
new file mode 100644
index 0000000..4af1c42
--- /dev/null
+++ b/apps/restconf/api/src/main/java/org/onosproject/restconf/api/Patch.java
@@ -0,0 +1,32 @@
+/*
+ * 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.restconf.api;
+
+import javax.ws.rs.HttpMethod;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Indicates that the annotated method responds to HTTP PATCH requests.
+ */
+@Target({ElementType.METHOD})
+@Retention(RetentionPolicy.RUNTIME)
+@HttpMethod("PATCH")
+public @interface Patch {
+}
\ No newline at end of file
diff --git a/apps/restconf/api/src/main/java/org/onosproject/restconf/api/RestconfException.java b/apps/restconf/api/src/main/java/org/onosproject/restconf/api/RestconfException.java
new file mode 100644
index 0000000..523c57e
--- /dev/null
+++ b/apps/restconf/api/src/main/java/org/onosproject/restconf/api/RestconfException.java
@@ -0,0 +1,67 @@
+/*
+ * 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.restconf.api;
+
+import javax.ws.rs.WebApplicationException;
+import javax.ws.rs.core.Response;
+
+import static javax.ws.rs.core.Response.Status;
+
+/**
+ * Exceptions raised during RESTCONF operations. This class extends
+ * WebApplicationException. The design intention is to create a place holder
+ * for RESTCONF specific errors and to be able to add more functions as the
+ * subsystem grows.
+ */
+public class RestconfException extends WebApplicationException {
+
+    // This is a randomly generated value. A WebApplicationException class is required to define it.
+    private static final long SERIAL_VERSION_UID = 3275970397584007046L;
+
+    /**
+     * Constructs a new RESTCONF server error exception. The caller raising this
+     * exception may pass in a HTTP error status code and an error message. The
+     * error code will be displayed to the RESTCONF client as part of the
+     * response from the RESTCONF server. The error message is a string which
+     * may be saved in a log file and may be later retrieved by the
+     * getMessage() method.
+     *
+     * @param message the detailed error message
+     * @param status  HTTP error status
+     * @throws IllegalArgumentException in case the status code is null or is not from
+     *                                  javax.ws.rs.core.Response.Status.Family
+     *                                  status code family
+     */
+    public RestconfException(String message, Status status) {
+        super(message, null, Response.status(status).build());
+    }
+
+    /**
+     * Constructs a new RESTCONF server error exception. The caller raising
+     * this exception may pass in the numerical value of a HTTP error
+     * status code, The error code will be displayed to the RESTCONF client
+     * as a response from the RESTCONF server.
+     *
+     * @param status HTTP error status
+     * @throws IllegalArgumentException in case the status code is not a valid
+     *                                  HTTP status code or if it is not from the
+     *                                  javax.ws.rs.core.Response.Status.Family
+     *                                  status code family
+     */
+    public RestconfException(int status) {
+        super((Throwable) null, Response.status(status).build());
+    }
+}
diff --git a/apps/restconf/api/src/main/java/org/onosproject/restconf/api/RestconfService.java b/apps/restconf/api/src/main/java/org/onosproject/restconf/api/RestconfService.java
new file mode 100644
index 0000000..f44ed99
--- /dev/null
+++ b/apps/restconf/api/src/main/java/org/onosproject/restconf/api/RestconfService.java
@@ -0,0 +1,130 @@
+/*
+ * 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.restconf.api;
+
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import org.glassfish.jersey.server.ChunkedOutput;
+
+/**
+ * Abstraction of RESTCONF Server functionality according to the
+ * RESTCONF RFC (no official RFC number yet).
+ */
+public interface RestconfService {
+    /**
+     * Processes a GET request against a data resource. The
+     * target data resource is identified by its URI. If the
+     * GET operation cannot be fulfilled due to reasons such
+     * as the nonexistence of the target resource, then a
+     * RestconfException exception is raised. The proper
+     * HTTP error status code is enclosed in the exception, so
+     * that the caller may return it to the RESTCONF client to
+     * display.
+     *
+     * @param uri URI of the target data resource
+     * @return JSON representation of the data resource
+     * @throws RestconfException if the GET operation cannot be fulfilled
+     */
+    ObjectNode runGetOperationOnDataResource(String uri)
+            throws RestconfException;
+
+    /**
+     * Processes a POST request against a data resource. The location of
+     * the target resource is passed in as a URI. And the resource's
+     * content is passed in as a JSON ObjectNode. If the POST operation
+     * cannot be fulfilled due to reasons such as wrong input URIs or
+     * syntax errors in the JSON payloads, a RestconfException exception
+     * is raised. The proper HTTP error status code is enclosed in the
+     * exception.
+     *
+     * @param uri      URI of the data resource to be created
+     * @param rootNode JSON representation of the data resource
+     * @throws RestconfException if the POST operation cannot be fulfilled
+     */
+    void runPostOperationOnDataResource(String uri, ObjectNode rootNode)
+            throws RestconfException;
+
+    /**
+     * Processes a PUT request against a data resource. The location of
+     * the target resource is passed in as a URI. And the resource's
+     * content is passed in as a JSON ObjectNode. If the PUT operation
+     * cannot be fulfilled due to reasons such as wrong input URIs or
+     * syntax errors in the JSON payloads, a RestconfException exception
+     * is raised. The proper HTTP error status code is enclosed in the
+     * exception.
+     *
+     * @param uri      URI of the data resource to be created or updated
+     * @param rootNode JSON representation of the data resource
+     * @throws RestconfException if the PUT operation cannot be fulfilled
+     */
+    void runPutOperationOnDataResource(String uri, ObjectNode rootNode)
+            throws RestconfException;
+
+    /**
+     * Processes the DELETE operation against a data resource. The target
+     * data resource is identified by its URI. If the DELETE operation
+     * cannot be fulfilled due reasons such as the nonexistence of the
+     * target resource, a RestconfException exception is raised. The
+     * proper HTTP error status code is enclosed in the exception.
+     *
+     * @param uri URI of the data resource to be deleted
+     * @throws RestconfException if the DELETE operation cannot be fulfilled
+     */
+    void runDeleteOperationOnDataResource(String uri) throws RestconfException;
+
+    /**
+     * Processes a PATCH operation on a data resource. The target data
+     * resource is identified by its URI passed in by the caller.
+     * And the content of the data resource is passed in as a JSON ObjectNode.
+     * If the PATCH operation cannot be fulfilled due reasons such as
+     * the nonexistence of the target resource, a RestconfException
+     * exception is raised. The proper HTTP error status code is
+     * enclosed in the exception.
+     *
+     * @param uri      URI of the data resource to be patched
+     * @param rootNode JSON representation of the data resource
+     * @throws RestconfException if the PATCH operation cannot be fulfilled
+     */
+    void runPatchOperationOnDataResource(String uri, ObjectNode rootNode)
+            throws RestconfException;
+
+    /**
+     * Retrieves the RESTCONF Root directory.
+     *
+     * @return the RESTCONF Root directory
+     */
+    String getRestconfRootPath();
+
+    /**
+     * Handles an Event Stream subscription request. This function creates
+     * a worker thread to listen to events and writes to a ChunkedOutput,
+     * which is passed in from the caller. (The worker thread blocks if
+     * no events arrive.) The ChuckedOutput is a pipe to which this
+     * function acts as the writer and the caller the reader.
+     * <p>
+     * If the Event Stream cannot be subscribed due to reasons such as
+     * the nonexistence of the target stream or failure to allocate
+     * worker thread to handle the request, a RestconfException exception
+     * is raised. The proper HTTP error status code is enclosed in the
+     * exception, so that the caller may return it to the RESTCONF client
+     * to display.
+     *
+     * @param streamId ID of the RESTCONF stream to subscribe
+     * @param output   A string data stream
+     * @throws RestconfException if the Event Stream cannot be subscribed
+     */
+    void subscribeEventStream(String streamId, ChunkedOutput<String> output)
+            throws RestconfException;
+}
diff --git a/apps/restconf/api/src/main/java/org/onosproject/restconf/api/package-info.java b/apps/restconf/api/src/main/java/org/onosproject/restconf/api/package-info.java
new file mode 100644
index 0000000..273e398
--- /dev/null
+++ b/apps/restconf/api/src/main/java/org/onosproject/restconf/api/package-info.java
@@ -0,0 +1,21 @@
+/*
+ * 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.
+ */
+
+/**
+ * RESTCONF Server Public Interface. All public interfaces/APIs that might be used by
+ * external applications should be packaged here.
+ */
+package org.onosproject.restconf.api;