diff --git a/apps/optical/src/main/java/org/onlab/onos/optical/testapp/LambdaForwarding.java b/apps/optical/src/main/java/org/onlab/onos/optical/testapp/LambdaForwarding.java
index b78501f..27b558c 100644
--- a/apps/optical/src/main/java/org/onlab/onos/optical/testapp/LambdaForwarding.java
+++ b/apps/optical/src/main/java/org/onlab/onos/optical/testapp/LambdaForwarding.java
@@ -83,8 +83,12 @@
         int inport;
         int outport;
         short lambda = 10;
+        byte sigType = 1;
+        Integer switchNumber = uglyMap.get(device.id());
+        if (switchNumber == null) {
+            return;
+        }
 
-        int switchNumber = uglyMap.get(device.id());
         switch (switchNumber) {
         case 1:
             inport = 10;
@@ -95,13 +99,15 @@
         case 2:
             inport = 21;
             outport = 11;
-            sbuilder.matchLambda(lambda).matchInport(PortNumber.portNumber(inport)); // match sigtype
+            sbuilder.matchLambda(lambda).
+                    matchInport(PortNumber.portNumber(inport)); // match sigtype
             tbuilder.setOutput(PortNumber.portNumber(outport));
             break;
         case 3:
             inport = 30;
             outport = 31;
-            sbuilder.matchLambda(lambda).matchInport(PortNumber.portNumber(inport));
+            sbuilder.matchLambda(lambda).
+                    matchInport(PortNumber.portNumber(inport));
             tbuilder.setOutput(PortNumber.portNumber(outport)).setLambda(lambda);
             break;
         default:
diff --git a/core/api/src/main/java/org/onlab/onos/net/flow/DefaultTrafficSelector.java b/core/api/src/main/java/org/onlab/onos/net/flow/DefaultTrafficSelector.java
index 63e7e24..b840318 100644
--- a/core/api/src/main/java/org/onlab/onos/net/flow/DefaultTrafficSelector.java
+++ b/core/api/src/main/java/org/onlab/onos/net/flow/DefaultTrafficSelector.java
@@ -176,11 +176,17 @@
         }
 
         @Override
-        public Builder matchLambda(short lambda) {
+        public Builder matchLambda(Short lambda) {
             return add(Criteria.matchLambda(lambda));
         }
 
         @Override
+        public Builder matchOpticalSignalType(Byte signalType) {
+            return add(Criteria.matchOpticalSignalType(signalType));
+
+        }
+
+        @Override
         public TrafficSelector build() {
             return new DefaultTrafficSelector(ImmutableSet.copyOf(selector.values()));
         }
diff --git a/core/api/src/main/java/org/onlab/onos/net/flow/TrafficSelector.java b/core/api/src/main/java/org/onlab/onos/net/flow/TrafficSelector.java
index 49815db..ab9b4a1 100644
--- a/core/api/src/main/java/org/onlab/onos/net/flow/TrafficSelector.java
+++ b/core/api/src/main/java/org/onlab/onos/net/flow/TrafficSelector.java
@@ -134,7 +134,14 @@
          * @param lambda
          * @return a selection builder
          */
-        public Builder matchLambda(short lambda);
+        public Builder matchLambda(Short lambda);
+
+        /**
+         * Matches an optical Signal Type.
+         * @param signalType
+         * @return a selection builder
+         */
+        public Builder matchOpticalSignalType(Byte signalType);
 
         /**
          * Builds an immutable traffic selector.
diff --git a/core/api/src/main/java/org/onlab/onos/net/flow/criteria/Criteria.java b/core/api/src/main/java/org/onlab/onos/net/flow/criteria/Criteria.java
index 2e177f7..9d8ab7b 100644
--- a/core/api/src/main/java/org/onlab/onos/net/flow/criteria/Criteria.java
+++ b/core/api/src/main/java/org/onlab/onos/net/flow/criteria/Criteria.java
@@ -162,6 +162,17 @@
     }
 
     /**
+     * Creates a match on lambda field using the specified value.
+     *
+     * @param lambda
+     * @return match criterion
+     */
+    public static Criterion matchOpticalSignalType(Byte lambda) {
+        return new OpticalSignalTypeCriterion(lambda, Type.OCH_SIGTYPE);
+    }
+
+
+    /**
      * Implementations of criteria.
      */
     public static final class PortCriterion implements Criterion {
@@ -577,4 +588,48 @@
         }
     }
 
+    public static final class OpticalSignalTypeCriterion implements Criterion {
+
+        private final byte signalType;
+        private final Type type;
+
+        public OpticalSignalTypeCriterion(byte signalType, Type type) {
+            this.signalType = signalType;
+            this.type = type;
+        }
+
+        @Override
+        public Type type() {
+            return this.type;
+        }
+
+        public Byte signalType() {
+            return this.signalType;
+        }
+
+        @Override
+        public String toString() {
+            return toStringHelper(type().toString())
+                    .add("signalType", signalType).toString();
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(signalType, type);
+        }
+
+        @Override
+        public boolean equals(Object obj) {
+            if (this == obj) {
+                return true;
+            }
+            if (obj instanceof OpticalSignalTypeCriterion) {
+                OpticalSignalTypeCriterion that = (OpticalSignalTypeCriterion) obj;
+                return Objects.equals(signalType, that.signalType) &&
+                        Objects.equals(type, that.type);
+            }
+            return false;
+        }
+    }
+
 }