diff --git a/core/api/src/main/java/org/onlab/onos/CoreService.java b/core/api/src/main/java/org/onlab/onos/CoreService.java
new file mode 100644
index 0000000..32c36c5
--- /dev/null
+++ b/core/api/src/main/java/org/onlab/onos/CoreService.java
@@ -0,0 +1,15 @@
+package org.onlab.onos;
+
+/**
+ * Service for interacting with the core system of the controller.
+ */
+public interface CoreService {
+
+    /**
+     * Returns the product version.
+     *
+     * @return product version
+     */
+    Version version();
+
+}
diff --git a/core/api/src/main/java/org/onlab/onos/Version.java b/core/api/src/main/java/org/onlab/onos/Version.java
new file mode 100644
index 0000000..5d071b7
--- /dev/null
+++ b/core/api/src/main/java/org/onlab/onos/Version.java
@@ -0,0 +1,113 @@
+package org.onlab.onos;
+
+import java.util.Objects;
+
+import static java.lang.Integer.parseInt;
+
+/**
+ * Representation of the product version.
+ */
+public final class Version {
+
+    public static final String FORMAT = "%d.%d.%d.%s";
+
+    private final int major;
+    private final int minor;
+    private final int patch;
+    private final String build;
+
+    private final String format;
+
+    // Creates a new version descriptor
+    private Version(int major, int minor, int patch, String build) {
+        this.major = major;
+        this.minor = minor;
+        this.patch = patch;
+        this.build = build;
+        this.format = String.format(FORMAT, major, minor, patch, build);
+    }
+
+
+    /**
+     * Creates a new version from the specified constituent numbers.
+     *
+     * @param major major version number
+     * @param minor minod version number
+     * @param patch version patch number
+     * @param build build string
+     * @return version descriptor
+     */
+    public static Version version(int major, int minor, int patch, String build) {
+        return new Version(major, minor, patch, build);
+    }
+
+    /**
+     * Creates a new version by parsing the specified string.
+     *
+     * @param string version string
+     * @return version descriptor
+     */
+    public static Version version(String string) {
+        String[] fields = string.split("[.-]");
+        return new Version(parseInt(fields[0]), parseInt(fields[1]),
+                           parseInt(fields[2]), fields[3]);
+    }
+
+    /**
+     * Returns the major version number.
+     *
+     * @return major version number
+     */
+    public int major() {
+        return major;
+    }
+
+    /**
+     * Returns the minor version number.
+     *
+     * @return minor version number
+     */
+    public int minor() {
+        return minor;
+    }
+
+    /**
+     * Returns the version patch number.
+     *
+     * @return patch number
+     */
+    public int patch() {
+        return patch;
+    }
+
+    /**
+     * Returns the version build string.
+     *
+     * @return build string
+     */
+    public String build() {
+        return build;
+    }
+
+    @Override
+    public String toString() {
+        return format;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(format);
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+        if (obj instanceof Version) {
+            final Version other = (Version) obj;
+            return Objects.equals(this.format, other.format);
+        }
+        return false;
+    }
+}
diff --git a/core/api/src/test/java/org/onlab/onos/VersionTest.java b/core/api/src/test/java/org/onlab/onos/VersionTest.java
new file mode 100644
index 0000000..e357f9d
--- /dev/null
+++ b/core/api/src/test/java/org/onlab/onos/VersionTest.java
@@ -0,0 +1,50 @@
+package org.onlab.onos;
+
+import com.google.common.testing.EqualsTester;
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+import static org.onlab.onos.Version.version;
+
+/**
+ * Tests of the version descriptor.
+ */
+public class VersionTest {
+
+    @Test
+    public void fromParts() {
+        Version v = version(1, 2, 3, "4321");
+        assertEquals("wrong major", 1, v.major());
+        assertEquals("wrong minor", 2, v.minor());
+        assertEquals("wrong patch", 3, v.patch());
+        assertEquals("wrong build", "4321", v.build());
+    }
+
+    @Test
+    public void fromString() {
+        Version v = version("1.2.3.4321");
+        assertEquals("wrong major", 1, v.major());
+        assertEquals("wrong minor", 2, v.minor());
+        assertEquals("wrong patch", 3, v.patch());
+        assertEquals("wrong build", "4321", v.build());
+    }
+
+    @Test
+    public void snapshot() {
+        Version v = version("1.2.3-SNAPSHOT");
+        assertEquals("wrong major", 1, v.major());
+        assertEquals("wrong minor", 2, v.minor());
+        assertEquals("wrong patch", 3, v.patch());
+        assertEquals("wrong build", "SNAPSHOT", v.build());
+    }
+
+    @Test
+    public void testEquals() {
+        new EqualsTester()
+                .addEqualityGroup(version("1.2.3.4321"), version(1, 2, 3, "4321"))
+                .addEqualityGroup(version("1.9.3.4321"), version(1, 9, 3, "4321"))
+                .addEqualityGroup(version("1.2.8.4321"), version(1, 2, 8, "4321"))
+                .addEqualityGroup(version("1.2.3.x"), version(1, 2, 3, "x"))
+                .testEquals();
+    }
+}
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