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 b4d566c..49815db 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
@@ -130,6 +130,13 @@
         public Builder matchTcpDst(Short tcpPort);
 
         /**
+         * Matches an optical signal ID or lambda.
+         * @param lambda
+         * @return a selection builder
+         */
+        public Builder matchLambda(short lambda);
+
+        /**
          * Builds an immutable traffic selector.
          *
          * @return traffic selector