diff --git a/core/api/src/main/java/org/onosproject/net/flow/instructions/L1ModificationInstruction.java b/core/api/src/main/java/org/onosproject/net/flow/instructions/L1ModificationInstruction.java
new file mode 100644
index 0000000..c6847d1
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/net/flow/instructions/L1ModificationInstruction.java
@@ -0,0 +1,88 @@
+/*
+ * Copyright 2014-2015 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.net.flow.instructions;
+
+import org.onosproject.net.OduSignalId;
+
+import static com.google.common.base.MoreObjects.toStringHelper;
+
+import java.util.Objects;
+
+public abstract class L1ModificationInstruction implements Instruction {
+
+    /**
+     * Represents the type of traffic treatment.
+     */
+    public enum L1SubType {
+        /**
+         * ODU (Optical channel Data Unit) Signal Id modification.
+         */
+        ODU_SIGID
+    }
+
+    public abstract L1SubType subtype();
+
+    @Override
+    public final Type type() {
+        return Type.L1MODIFICATION;
+    }
+
+    /**
+     * Represents an L1 ODU (Optical channel Data Unit) Signal Id modification instruction.
+     */
+    public static final class ModOduSignalIdInstruction extends L1ModificationInstruction {
+
+        private final OduSignalId oduSignalId;
+
+        ModOduSignalIdInstruction(OduSignalId oduSignalId) {
+            this.oduSignalId = oduSignalId;
+        }
+
+        @Override
+        public L1SubType subtype() {
+            return L1SubType.ODU_SIGID;
+        }
+
+        public OduSignalId oduSignalId() {
+            return oduSignalId;
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(oduSignalId);
+        }
+
+        @Override
+        public boolean equals(Object obj) {
+            if (this == obj) {
+                return true;
+            }
+            if (!(obj instanceof ModOduSignalIdInstruction)) {
+                return false;
+            }
+            final ModOduSignalIdInstruction that = (ModOduSignalIdInstruction) obj;
+            return Objects.equals(this.oduSignalId, that.oduSignalId);
+        }
+
+        @Override
+        public String toString() {
+            return toStringHelper(this)
+                    .add("oduSignalId", oduSignalId)
+                    .toString();
+        }
+    }
+
+}