diff --git a/drivers/oplink/src/main/java/org/onosproject/drivers/oplink/OplinkOpticalUtility.java b/drivers/oplink/src/main/java/org/onosproject/drivers/oplink/OplinkOpticalUtility.java
new file mode 100644
index 0000000..9785224
--- /dev/null
+++ b/drivers/oplink/src/main/java/org/onosproject/drivers/oplink/OplinkOpticalUtility.java
@@ -0,0 +1,182 @@
+/*
+ * Copyright 2016 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.drivers.oplink;
+
+import org.onlab.util.Frequency;
+import org.onosproject.core.CoreService;
+import org.onosproject.driver.extensions.OplinkAttenuation;
+import org.onosproject.net.ChannelSpacing;
+import org.onosproject.net.GridType;
+import org.onosproject.net.Lambda;
+import org.onosproject.net.OchSignalType;
+import org.onosproject.net.PortNumber;
+import org.onosproject.net.driver.HandlerBehaviour;
+import org.onosproject.net.flow.DefaultFlowRule;
+import org.onosproject.net.flow.DefaultTrafficSelector;
+import org.onosproject.net.flow.DefaultTrafficTreatment;
+import org.onosproject.net.flow.FlowEntry;
+import org.onosproject.net.flow.FlowRule;
+import org.onosproject.net.flow.FlowRuleService;
+import org.onosproject.net.flow.TrafficSelector;
+import org.onosproject.net.flow.TrafficTreatment;
+import org.onosproject.net.flow.criteria.Criteria;
+import org.onosproject.net.flow.criteria.Criterion;
+import org.onosproject.net.flow.criteria.OchSignalCriterion;
+import org.onosproject.net.flow.criteria.PortCriterion;
+import org.onosproject.net.flow.instructions.Instruction;
+import org.onosproject.net.flow.instructions.Instructions;
+
+import java.util.List;
+import java.util.Set;
+
+/**
+ * Oplink optical utilities.
+ */
+public final class OplinkOpticalUtility {
+
+    // Lambda information supported by device.
+    public static final GridType GRID_TYPE = GridType.DWDM;
+    public static final int SLOT_GRANULARITY = 4;
+    // Channel spacing is 50GHz, 12.5GHz * 4
+    public static final ChannelSpacing CHANNEL_SPACING = ChannelSpacing.CHL_50GHZ;
+    // Start frequency supported by device.
+    public static final Frequency START_CENTER_FREQ = Frequency.ofGHz(191_350);
+    // Stop frequency supported by device.
+    public static final Frequency STOP_CENTER_FREQ = Frequency.ofGHz(196_100);
+
+    // Power multiply factor, the power accuracy supported by device is 0.01dBm.
+    // Transforms the double typed number to long typed power for ONOS.
+    public static final int POWER_MULTIPLIER = 100;
+    // Attenuation range supported by device, [0, 25dB].
+    public static final long MIN_ATTENUATION = 0L;
+    public static final long MAX_ATTENUATION = 2500L;
+
+    // Default attenuation value if the attenuation instruction is not found.
+    private static final int DEFAULT_ATT = 0;
+    // Default flow priority for an extra flow.
+    private static final int DEFAULT_PRIORITY = 88;
+    // Default application name.
+    private static final String DEFAULT_APP = "org.onosproject.drivers.oplink";
+
+    private OplinkOpticalUtility() {
+    }
+
+    /**
+     * Transforms a flow FlowRule object to an OplinkCrossConnect object.
+     * @param behaviour the parent driver handler
+     * @param rule FlowRule object
+     * @return cross connect object
+     */
+    public static OplinkCrossConnect fromFlowRule(HandlerBehaviour behaviour, FlowRule rule) {
+        // TrafficSelector
+        Set<Criterion> criterions = rule.selector().criteria();
+        int channel = criterions.stream()
+                .filter(c -> c instanceof OchSignalCriterion)
+                .map(c -> ((OchSignalCriterion) c).lambda().spacingMultiplier())
+                .findAny()
+                .orElse(null);
+        PortNumber inPort = criterions.stream()
+                .filter(c -> c instanceof PortCriterion)
+                .map(c -> ((PortCriterion) c).port())
+                .findAny()
+                .orElse(null);
+        // TrafficTreatment
+        List<Instruction> instructions = rule.treatment().immediate();
+        PortNumber outPort = instructions.stream()
+                .filter(c -> c instanceof Instructions.OutputInstruction)
+                .map(c -> ((Instructions.OutputInstruction) c).port())
+                .findAny()
+                .orElse(null);
+        int attenuation = instructions.stream()
+                .filter(c -> c instanceof Instructions.ExtensionInstructionWrapper)
+                .map(c -> ((Instructions.ExtensionInstructionWrapper) c).extensionInstruction())
+                .filter(c -> c instanceof OplinkAttenuation)
+                .map(c -> ((OplinkAttenuation) c).getAttenuation())
+                .findAny()
+                .orElse(DEFAULT_ATT);
+        return new OplinkCrossConnect(inPort, outPort, channel, attenuation);
+    }
+
+    /**
+     * Finds the FlowRule from flow rule store by the given cross connect information.
+     * Returns an extra flow to remove the flow by ONOS if not found.
+     * @param behaviour the parent driver handler
+     * @param cfg cross connect information
+     * @return the flow rule
+     */
+    public static FlowRule toFlowRule(HandlerBehaviour behaviour, OplinkCrossConnect cfg) {
+        return toFlowRule(behaviour, cfg.getInPort(), cfg.getOutPort(), cfg.getChannel());
+    }
+
+    /**
+     * Finds the FlowRule from flow rule store by the given ports and channel.
+     * Returns an extra flow to remove the flow by ONOS if not found.
+     * @param behaviour the parent driver handler
+     * @param inPort the input port
+     * @param outPort the output port
+     * @param channel the specified channel
+     * @return the flow rule
+     */
+    public static FlowRule toFlowRule(HandlerBehaviour behaviour, PortNumber inPort,
+                                      PortNumber outPort, Integer channel) {
+        FlowRuleService service = behaviour.handler().get(FlowRuleService.class);
+        Iterable<FlowEntry> entries = service.getFlowEntries(behaviour.data().deviceId());
+        // Try to Find the flow from flow rule store.
+        for (FlowEntry entry : entries) {
+            Set<Criterion> criterions = entry.selector().criteria();
+            // input port
+            PortNumber ip = criterions.stream()
+                    .filter(c -> c instanceof PortCriterion)
+                    .map(c -> ((PortCriterion) c).port())
+                    .findAny()
+                    .orElse(null);
+            // channel
+            Integer ch = criterions.stream()
+                    .filter(c -> c instanceof OchSignalCriterion)
+                    .map(c -> ((OchSignalCriterion) c).lambda().spacingMultiplier())
+                    .findAny()
+                    .orElse(null);
+            // output port
+            PortNumber op = entry.treatment().immediate().stream()
+                    .filter(c -> c instanceof Instructions.OutputInstruction)
+                    .map(c -> ((Instructions.OutputInstruction) c).port())
+                    .findAny()
+                    .orElse(null);
+            if (inPort.equals(ip) && channel.equals(ch) && outPort.equals(op)) {
+                // Find the flow.
+                return entry;
+            }
+        }
+        // Cannot find the flow from store. So report an extra flow to remove the flow by ONOS.
+        TrafficSelector selector = DefaultTrafficSelector.builder()
+                .matchInPort(inPort)
+                .add(Criteria.matchOchSignalType(OchSignalType.FIXED_GRID))
+                .add(Criteria.matchLambda(Lambda.ochSignal(GRID_TYPE, CHANNEL_SPACING, channel, SLOT_GRANULARITY)))
+                .build();
+        TrafficTreatment treatment = DefaultTrafficTreatment.builder()
+                .setOutput(outPort)
+                .build();
+        return DefaultFlowRule.builder()
+                .forDevice(behaviour.data().deviceId())
+                .withSelector(selector)
+                .withTreatment(treatment)
+                .withPriority(DEFAULT_PRIORITY)
+                .fromApp(behaviour.handler().get(CoreService.class).getAppId(DEFAULT_APP))
+                .build();
+
+    }
+}