diff --git a/core/common/src/main/java/org/onosproject/codec/impl/DecodeInstructionCodecHelper.java b/core/common/src/main/java/org/onosproject/codec/impl/DecodeInstructionCodecHelper.java
index 568fa76..6a97a07 100644
--- a/core/common/src/main/java/org/onosproject/codec/impl/DecodeInstructionCodecHelper.java
+++ b/core/common/src/main/java/org/onosproject/codec/impl/DecodeInstructionCodecHelper.java
@@ -18,19 +18,21 @@
 import org.onlab.packet.IpAddress;
 import org.onlab.packet.MacAddress;
 import org.onlab.packet.MplsLabel;
+import org.onlab.packet.TpPort;
 import org.onlab.packet.VlanId;
 import org.onosproject.net.ChannelSpacing;
 import org.onosproject.net.GridType;
 import org.onosproject.net.Lambda;
 import org.onosproject.net.OchSignal;
 import org.onosproject.net.PortNumber;
+
+import com.fasterxml.jackson.databind.node.ObjectNode;
 import org.onosproject.net.flow.instructions.Instruction;
 import org.onosproject.net.flow.instructions.Instructions;
 import org.onosproject.net.flow.instructions.L0ModificationInstruction;
 import org.onosproject.net.flow.instructions.L2ModificationInstruction;
 import org.onosproject.net.flow.instructions.L3ModificationInstruction;
-
-import com.fasterxml.jackson.databind.node.ObjectNode;
+import org.onosproject.net.flow.instructions.L4ModificationInstruction;
 
 import static org.onlab.util.Tools.nullIsIllegal;
 
@@ -172,6 +174,36 @@
     }
 
     /**
+     * Decodes a Layer 4 instruction.
+     *
+     * @return instruction object decoded from the JSON
+     * @throws IllegalArgumentException if the JSON is invalid
+     */
+    private Instruction decodeL4() {
+        String subType = json.get(InstructionCodec.SUBTYPE).asText();
+
+        if (subType.equals(L4ModificationInstruction.L4SubType.TCP_DST.name())) {
+            TpPort tcpPort = TpPort.tpPort(nullIsIllegal(json.get(InstructionCodec.TCP_PORT),
+                    InstructionCodec.TCP_PORT + InstructionCodec.MISSING_MEMBER_MESSAGE).asInt());
+            return Instructions.modTcpDst(tcpPort);
+        } else if (subType.equals(L4ModificationInstruction.L4SubType.TCP_SRC.name())) {
+            TpPort tcpPort = TpPort.tpPort(nullIsIllegal(json.get(InstructionCodec.TCP_PORT),
+                    InstructionCodec.TCP_PORT + InstructionCodec.MISSING_MEMBER_MESSAGE).asInt());
+            return Instructions.modTcpSrc(tcpPort);
+        } else if (subType.equals(L4ModificationInstruction.L4SubType.UDP_DST.name())) {
+            TpPort udpPort = TpPort.tpPort(nullIsIllegal(json.get(InstructionCodec.UDP_PORT),
+                    InstructionCodec.UDP_PORT + InstructionCodec.MISSING_MEMBER_MESSAGE).asInt());
+            return Instructions.modUdpDst(udpPort);
+        } else if (subType.equals(L4ModificationInstruction.L4SubType.UDP_SRC.name())) {
+            TpPort udpPort = TpPort.tpPort(nullIsIllegal(json.get(InstructionCodec.UDP_PORT),
+                    InstructionCodec.UDP_PORT + InstructionCodec.MISSING_MEMBER_MESSAGE).asInt());
+            return Instructions.modUdpSrc(udpPort);
+        }
+        throw new IllegalArgumentException("L4 Instruction subtype "
+                + subType + " is not supported");
+    }
+
+    /**
      * Decodes the JSON into an instruction object.
      *
      * @return Criterion object
@@ -193,6 +225,8 @@
             return decodeL2();
         } else if (type.equals(Instruction.Type.L3MODIFICATION.name())) {
             return decodeL3();
+        } else if (type.equals(Instruction.Type.L4MODIFICATION.name())) {
+            return decodeL4();
         }
         throw new IllegalArgumentException("Instruction type "
                 + type + " is not supported");
diff --git a/core/common/src/main/java/org/onosproject/codec/impl/EncodeInstructionCodecHelper.java b/core/common/src/main/java/org/onosproject/codec/impl/EncodeInstructionCodecHelper.java
index 6927680..8a4dfa5 100644
--- a/core/common/src/main/java/org/onosproject/codec/impl/EncodeInstructionCodecHelper.java
+++ b/core/common/src/main/java/org/onosproject/codec/impl/EncodeInstructionCodecHelper.java
@@ -22,6 +22,7 @@
 import org.onosproject.net.flow.instructions.L0ModificationInstruction;
 import org.onosproject.net.flow.instructions.L2ModificationInstruction;
 import org.onosproject.net.flow.instructions.L3ModificationInstruction;
+import org.onosproject.net.flow.instructions.L4ModificationInstruction;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -168,6 +169,36 @@
     }
 
     /**
+     * Encode a L4 modification instruction.
+     *
+     * @param result json node that the instruction attributes are added to
+     */
+    private void encodeL4(ObjectNode result) {
+        L4ModificationInstruction instruction =
+                (L4ModificationInstruction) this.instruction;
+        result.put(InstructionCodec.SUBTYPE, instruction.subtype().name());
+        switch (instruction.subtype()) {
+            case TCP_DST:
+            case TCP_SRC:
+                final L4ModificationInstruction.ModTransportPortInstruction modTcpPortInstruction =
+                        (L4ModificationInstruction.ModTransportPortInstruction) instruction;
+                result.put(InstructionCodec.TCP_PORT, modTcpPortInstruction.port().toInt());
+                break;
+
+            case UDP_DST:
+            case UDP_SRC:
+                final L4ModificationInstruction.ModTransportPortInstruction modUdpPortInstruction =
+                        (L4ModificationInstruction.ModTransportPortInstruction) instruction;
+                result.put(InstructionCodec.UDP_PORT, modUdpPortInstruction.port().toInt());
+                break;
+
+            default:
+                log.info("Cannot convert L4 subtype of {}", instruction.subtype());
+                break;
+        }
+    }
+
+    /**
      * Encodes the given instruction into JSON.
      *
      * @return JSON object node representing the instruction
@@ -198,6 +229,10 @@
                 encodeL3(result);
                 break;
 
+            case L4MODIFICATION:
+                encodeL4(result);
+                break;
+
             default:
                 log.info("Cannot convert instruction type of {}", instruction.type());
                 break;
diff --git a/core/common/src/main/java/org/onosproject/codec/impl/InstructionCodec.java b/core/common/src/main/java/org/onosproject/codec/impl/InstructionCodec.java
index 6fa4ae0..f4d5008 100644
--- a/core/common/src/main/java/org/onosproject/codec/impl/InstructionCodec.java
+++ b/core/common/src/main/java/org/onosproject/codec/impl/InstructionCodec.java
@@ -48,6 +48,8 @@
     protected static final String SLOT_GRANULARITY = "slotGranularity";
     protected static final String ETHERNET_TYPE = "ethernetType";
     protected static final String TUNNEL_ID = "tunnelId";
+    protected static final String TCP_PORT = "tcpPort";
+    protected static final String UDP_PORT = "udpPort";
 
     protected static final String MISSING_MEMBER_MESSAGE =
             " member is required in Instruction";