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 8f68ea5..d792c7e 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
@@ -3,8 +3,9 @@
 import static org.slf4j.LoggerFactory.getLogger;
 
 import java.util.Collections;
-import java.util.LinkedList;
-import java.util.List;
+import java.util.HashSet;
+import java.util.Objects;
+import java.util.Set;
 
 import org.onlab.onos.net.PortNumber;
 import org.onlab.onos.net.flow.criteria.Criteria;
@@ -16,22 +17,42 @@
 
 public final class DefaultTrafficSelector implements TrafficSelector {
 
-    private final List<Criterion> selector;
+    private final Set<Criterion> selector;
 
-    private DefaultTrafficSelector(List<Criterion> selector) {
-        this.selector = Collections.unmodifiableList(selector);
+    private DefaultTrafficSelector(Set<Criterion> selector) {
+        this.selector = Collections.unmodifiableSet(selector);
     }
 
     @Override
-    public List<Criterion> criteria() {
+    public Set<Criterion> criteria() {
         return selector;
     }
 
+    @Override
+    public int hashCode() {
+        return Objects.hash(selector);
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+        if (obj instanceof DefaultTrafficSelector) {
+            DefaultTrafficSelector that = (DefaultTrafficSelector) obj;
+            return Objects.equals(selector, that.selector);
+
+        }
+        return false;
+    }
+
+
+
     public static class Builder implements TrafficSelector.Builder {
 
         private final Logger log = getLogger(getClass());
 
-        private final List<Criterion> selector = new LinkedList<>();
+        private final Set<Criterion> selector = new HashSet<>();
 
         @Override
         public Builder add(Criterion criterion) {
@@ -39,38 +60,47 @@
             return this;
         }
 
+        @Override
         public Builder matchInport(PortNumber port) {
             return add(Criteria.matchInPort(port));
         }
 
+        @Override
         public Builder matchEthSrc(MacAddress addr) {
             return add(Criteria.matchEthSrc(addr));
         }
 
+        @Override
         public Builder matchEthDst(MacAddress addr) {
             return add(Criteria.matchEthDst(addr));
         }
 
+        @Override
         public Builder matchEthType(short ethType) {
             return add(Criteria.matchEthType(ethType));
         }
 
+        @Override
         public Builder matchVlanId(VlanId vlanId) {
             return add(Criteria.matchVlanId(vlanId));
         }
 
+        @Override
         public Builder matchVlanPcp(Byte vlanPcp) {
             return add(Criteria.matchVlanPcp(vlanPcp));
         }
 
+        @Override
         public Builder matchIPProtocol(Byte proto) {
             return add(Criteria.matchIPProtocol(proto));
         }
 
+        @Override
         public Builder matchIPSrc(IpPrefix ip) {
             return add(Criteria.matchIPSrc(ip));
         }
 
+        @Override
         public Builder matchIPDst(IpPrefix ip) {
             return add(Criteria.matchIPDst(ip));
         }