diff --git a/rw_core/core/device/extension_manager.go b/rw_core/core/device/extension_manager.go
new file mode 100644
index 0000000..1e44ddf
--- /dev/null
+++ b/rw_core/core/device/extension_manager.go
@@ -0,0 +1,71 @@
+/*
+ * Copyright 2018-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 device
+
+import (
+	"context"
+	"github.com/opencord/voltha-lib-go/v4/pkg/log"
+	"github.com/opencord/voltha-protos/v4/go/extension"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+)
+
+type ExtensionManager struct {
+	DeviceManager *Manager
+}
+
+func GetNewExtensionManager(deviceManager *Manager) *ExtensionManager {
+	return &ExtensionManager{DeviceManager: deviceManager}
+}
+
+func (e ExtensionManager) GetExtValue(ctx context.Context, request *extension.SingleGetValueRequest) (*extension.SingleGetValueResponse, error) {
+	log.EnrichSpan(ctx, log.Fields{"device-id": request.TargetId})
+
+	logger.Debugw(ctx, "GetExtValue", log.Fields{"request": request})
+	agent := e.DeviceManager.getDeviceAgent(ctx, request.TargetId)
+	if agent == nil {
+		return nil, status.Errorf(codes.NotFound, "target-id %s", request.TargetId)
+	}
+
+	response, err := agent.getSingleValue(ctx, request)
+	if err != nil {
+		logger.Errorw(ctx, "Fail-to-get-single-value", log.Fields{"device-id": agent.deviceID, "error": err})
+		return nil, err
+	}
+
+	logger.Debugw(ctx, "GetExtValue response", log.Fields{"response": response})
+	return response, nil
+}
+
+func (e ExtensionManager) SetExtValue(ctx context.Context, request *extension.SingleSetValueRequest) (*extension.SingleSetValueResponse, error) {
+	log.EnrichSpan(ctx, log.Fields{"device-id": request.TargetId})
+
+	logger.Debugw(ctx, "SetExtValue", log.Fields{"request": request})
+	agent := e.DeviceManager.getDeviceAgent(ctx, request.TargetId)
+	if agent == nil {
+		return nil, status.Errorf(codes.NotFound, "target-id %s", request.TargetId)
+	}
+
+	response, err := agent.setSingleValue(ctx, request)
+	if err != nil {
+		logger.Errorw(ctx, "Fail-to-set-single-value", log.Fields{"device-id": agent.deviceID, "error": err})
+		return nil, err
+	}
+
+	logger.Debugw(ctx, "SetExtValue response", log.Fields{"response": response})
+	return response, nil
+}