diff --git a/internal/pkg/core/l2oam/onu_msg_set_encryption_mode.go b/internal/pkg/core/l2oam/onu_msg_set_encryption_mode.go
new file mode 100644
index 0000000..599e8d4
--- /dev/null
+++ b/internal/pkg/core/l2oam/onu_msg_set_encryption_mode.go
@@ -0,0 +1,61 @@
+/*
+ * Copyright 2020-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 l2oam
+
+import (
+	"github.com/google/gopacket"
+)
+
+// GenerateEncryptionMode generates "Encryption Mode" message
+func GenerateEncryptionMode(PkgType string, index int) gopacket.SerializableLayer {
+
+	if PkgType == OnuPkgTypeA {
+		//TypeA
+		if index == 1 {
+			data := &TibitFrame{
+				Data: []byte{
+					0x03, 0x00, 0x50, 0xfe, 0x00, 0x10, 0x00, 0x03,
+					0xd6, 0x00, 0x02, 0x01, 0x00, 0xd7, 0x04, 0x01,
+					0x02, 0x01, 0x2c, 0x00, 0x00,
+				},
+			}
+			return data
+		} else if index == 2 {
+			data := &TibitFrame{
+				Data: []byte{
+					0x03, 0x00, 0x50, 0xfe, 0x00, 0x10, 0x00, 0x03,
+					0xd6, 0x00, 0x02, 0x01, 0x00, 0xd7, 0x04, 0x02,
+					0x01, 0x02, 0x00, 0x00,
+				},
+			}
+			return data
+		}
+	} else if PkgType == OnuPkgTypeB {
+		//TypeB
+		if index == 1 {
+			data := &TibitFrame{
+				Data: []byte{
+					0x03, 0x00, 0x50, 0xfe, 0x90, 0x82, 0x60, 0x03,
+					0xca, 0xfe, 0x00, 0xb7, 0x00, 0x01, 0x01, 0x02,
+				},
+			}
+			return data
+		}
+	}
+
+	return nil
+}