diff --git a/core/api/src/main/java/org/onosproject/net/pi/runtime/PiMatchKey.java b/core/api/src/main/java/org/onosproject/net/pi/runtime/PiMatchKey.java
new file mode 100644
index 0000000..c95afb7
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/net/pi/runtime/PiMatchKey.java
@@ -0,0 +1,137 @@
+/*
+ * Copyright 2017-present 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.net.pi.runtime;
+
+import com.google.common.annotations.Beta;
+import com.google.common.base.Objects;
+import com.google.common.collect.ImmutableMap;
+
+import java.util.Collection;
+import java.util.Optional;
+import java.util.StringJoiner;
+
+import static com.google.common.base.Preconditions.checkArgument;
+
+/**
+ * Representation of all field matches of an entry of a match+action table of a protocol-independent pipeline.
+ */
+@Beta
+public final class PiMatchKey {
+
+    private final ImmutableMap<PiHeaderFieldId, PiFieldMatch> fieldMatches;
+
+    private PiMatchKey(ImmutableMap<PiHeaderFieldId, PiFieldMatch> fieldMatches) {
+        this.fieldMatches = fieldMatches;
+    }
+
+    /**
+     * Returns the collection of field matches of this match key.
+     *
+     * @return collection of field matches
+     */
+    public Collection<PiFieldMatch> fieldMatches() {
+        return fieldMatches.values();
+    }
+
+    /**
+     * If present, returns the field match associated with the given header field identifier.
+     *
+     * @param fieldId field identifier
+     * @return optional field match
+     */
+    public Optional<PiFieldMatch> fieldMatch(PiHeaderFieldId fieldId) {
+        return Optional.ofNullable(fieldMatches.get(fieldId));
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (!(o instanceof PiMatchKey)) {
+            return false;
+        }
+        PiMatchKey that = (PiMatchKey) o;
+        return Objects.equal(fieldMatches, that.fieldMatches);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hashCode(fieldMatches);
+    }
+
+    @Override
+    public String toString() {
+        StringJoiner stringFieldMatches = new StringJoiner(", ", "{", "}");
+        this.fieldMatches.values().forEach(f -> stringFieldMatches.add(f.toString()));
+        return stringFieldMatches.toString();
+    }
+
+    /**
+     * Returns a new builder of match keys.
+     *
+     * @return match key builder
+     */
+    public static Builder builder() {
+        return new Builder();
+    }
+
+    /**
+     * Builder of match keys.
+     */
+    public static final class Builder {
+
+        private final ImmutableMap.Builder<PiHeaderFieldId, PiFieldMatch> fieldMatchesBuilder = ImmutableMap.builder();
+
+        private Builder() {
+            // hides constructor.
+        }
+
+        /**
+         * Adds one field match to this match key.
+         *
+         * @param fieldMatch field match
+         * @return this
+         */
+        public Builder addFieldMatch(PiFieldMatch fieldMatch) {
+            this.fieldMatchesBuilder.put(fieldMatch.fieldId(), fieldMatch);
+            return this;
+        }
+
+        /**
+         * Adds many field matches to this match key.
+         *
+         * @param fieldMatches collection of field matches
+         * @return this
+         */
+        public Builder addFieldMatches(Collection<PiFieldMatch> fieldMatches) {
+            fieldMatches.forEach(this::addFieldMatch);
+            return this;
+        }
+
+        /**
+         * Creates a new match key.
+         *
+         * @return match key
+         */
+        public PiMatchKey build() {
+            ImmutableMap<PiHeaderFieldId, PiFieldMatch> fieldMatches = fieldMatchesBuilder.build();
+            checkArgument(fieldMatches.size() > 0, "Field matches cannot be empty");
+            return new PiMatchKey(fieldMatches);
+        }
+    }
+}
diff --git a/core/api/src/main/java/org/onosproject/net/pi/runtime/PiTableEntry.java b/core/api/src/main/java/org/onosproject/net/pi/runtime/PiTableEntry.java
index 63e478d..40b2f05 100644
--- a/core/api/src/main/java/org/onosproject/net/pi/runtime/PiTableEntry.java
+++ b/core/api/src/main/java/org/onosproject/net/pi/runtime/PiTableEntry.java
@@ -19,11 +19,7 @@
 import com.google.common.annotations.Beta;
 import com.google.common.base.MoreObjects;
 import com.google.common.base.Objects;
-import com.google.common.collect.ImmutableMap;
-import com.google.common.collect.Maps;
 
-import java.util.Collection;
-import java.util.Map;
 import java.util.Optional;
 
 import static com.google.common.base.Preconditions.checkArgument;
@@ -39,16 +35,16 @@
     private static final double NO_TIMEOUT = -1;
 
     private final PiTableId tableId;
-    private final Map<PiHeaderFieldId, PiFieldMatch> fieldMatches;
+    private final PiMatchKey matchKey;
     private final PiTableAction tableAction;
     private final long cookie;
     private final int priority;
     private final double timeout;
 
-    private PiTableEntry(PiTableId tableId, Map<PiHeaderFieldId, PiFieldMatch> fieldMatches,
+    private PiTableEntry(PiTableId tableId, PiMatchKey matchKey,
                          PiTableAction tableAction, long cookie, int priority, double timeout) {
         this.tableId = tableId;
-        this.fieldMatches = ImmutableMap.copyOf(fieldMatches);
+        this.matchKey = matchKey;
         this.tableAction = tableAction;
         this.cookie = cookie;
         this.priority = priority;
@@ -65,22 +61,12 @@
     }
 
     /**
-     * Returns an immutable view of the field matches of this table entry.
+     * Returns the match key of this table entry.
      *
-     * @return collection of field matches
+     * @return match key
      */
-    public Collection<PiFieldMatch> fieldMatches() {
-        return fieldMatches.values();
-    }
-
-    /**
-     * If present, returns the field match associated with the given header field identifier.
-     *
-     * @param fieldId field identifier
-     * @return optional field match
-     */
-    public Optional<PiFieldMatch> fieldMatch(PiHeaderFieldId fieldId) {
-        return Optional.ofNullable(fieldMatches.get(fieldId));
+    public PiMatchKey matchKey() {
+        return matchKey;
     }
 
     /**
@@ -133,20 +119,20 @@
         return priority == that.priority &&
                 Double.compare(that.timeout, timeout) == 0 &&
                 Objects.equal(tableId, that.tableId) &&
-                Objects.equal(fieldMatches, that.fieldMatches) &&
+                Objects.equal(matchKey, that.matchKey) &&
                 Objects.equal(tableAction, that.tableAction);
     }
 
     @Override
     public int hashCode() {
-        return Objects.hashCode(tableId, fieldMatches, tableAction, priority, timeout);
+        return Objects.hashCode(tableId, matchKey, tableAction, priority, timeout);
     }
 
     @Override
     public String toString() {
         return MoreObjects.toStringHelper(this)
                 .add("tableId", tableId)
-                .add("fieldMatches", fieldMatches)
+                .add("matchKey", matchKey)
                 .add("tableAction", tableAction)
                 .add("priority", priority == NO_PRIORITY ? "N/A" : String.valueOf(priority))
                 .add("timeout", timeout == NO_TIMEOUT ? "PERMANENT" : String.valueOf(timeout))
@@ -165,7 +151,7 @@
     public static final class Builder {
 
         private PiTableId tableId;
-        private Map<PiHeaderFieldId, PiFieldMatch> fieldMatches = Maps.newHashMap();
+        private PiMatchKey matchKey;
         private PiTableAction tableAction;
         private long cookie = 0;
         private int priority = NO_PRIORITY;
@@ -198,24 +184,13 @@
         }
 
         /**
-         * Adds one field match to this table entry.
+         * Sets the match key of this table entry.
          *
-         * @param fieldMatch field match
+         * @param matchKey match key
          * @return this
          */
-        public Builder withFieldMatch(PiFieldMatch fieldMatch) {
-            this.fieldMatches.put(fieldMatch.fieldId(), fieldMatch);
-            return this;
-        }
-
-        /**
-         * Adds many field matches to this table entry.
-         *
-         * @param fieldMatches collection of field matches
-         * @return this
-         */
-        public Builder withFieldMatches(Collection<PiFieldMatch> fieldMatches) {
-            fieldMatches.forEach(f -> this.fieldMatches.put(f.fieldId(), f));
+        public Builder withMatchKey(PiMatchKey matchKey) {
+            this.matchKey = matchKey;
             return this;
         }
 
@@ -262,7 +237,7 @@
         public PiTableEntry build() {
             checkNotNull(tableId);
             checkNotNull(tableAction);
-            return new PiTableEntry(tableId, fieldMatches, tableAction, cookie, priority, timeout);
+            return new PiTableEntry(tableId, matchKey, tableAction, cookie, priority, timeout);
         }
     }
 }