diff --git a/networksecurity/service/src/com/android/server/net/ct/CertificateTransparencyDownloader.java b/networksecurity/service/src/com/android/server/net/ct/CertificateTransparencyDownloader.java
index fb42c03..41b58fa 100644
--- a/networksecurity/service/src/com/android/server/net/ct/CertificateTransparencyDownloader.java
+++ b/networksecurity/service/src/com/android/server/net/ct/CertificateTransparencyDownloader.java
@@ -33,8 +33,7 @@
 import java.io.IOException;
 import java.io.InputStream;
 import java.security.GeneralSecurityException;
-import java.util.ArrayList;
-import java.util.List;
+import java.util.Collection;
 import java.util.Optional;
 
 /** Helper class to download certificate transparency log files. */
@@ -48,28 +47,21 @@
     private final DownloadHelper mDownloadHelper;
     private final SignatureVerifier mSignatureVerifier;
     private final CertificateTransparencyLogger mLogger;
-
-    private final List<CompatibilityVersion> mCompatVersions = new ArrayList<>();
+    private final Collection<CompatibilityVersion> mCompatVersions;
 
     CertificateTransparencyDownloader(
             Context context,
             DataStore dataStore,
             DownloadHelper downloadHelper,
             SignatureVerifier signatureVerifier,
-            CertificateTransparencyLogger logger) {
+            CertificateTransparencyLogger logger,
+            Collection<CompatibilityVersion> compatVersions) {
         mContext = context;
         mSignatureVerifier = signatureVerifier;
         mDataStore = dataStore;
         mDownloadHelper = downloadHelper;
         mLogger = logger;
-    }
-
-    void addCompatibilityVersion(CompatibilityVersion compatVersion) {
-        mCompatVersions.add(compatVersion);
-    }
-
-    void clearCompatibilityVersions() {
-        mCompatVersions.clear();
+        mCompatVersions = compatVersions;
     }
 
     long startPublicKeyDownload() {
diff --git a/networksecurity/service/src/com/android/server/net/ct/CertificateTransparencyJob.java b/networksecurity/service/src/com/android/server/net/ct/CertificateTransparencyJob.java
index f1b9a4f..286f326 100644
--- a/networksecurity/service/src/com/android/server/net/ct/CertificateTransparencyJob.java
+++ b/networksecurity/service/src/com/android/server/net/ct/CertificateTransparencyJob.java
@@ -28,6 +28,8 @@
 import android.os.SystemClock;
 import android.util.Log;
 
+import java.util.Collection;
+
 /** Implementation of the Certificate Transparency job */
 @RequiresApi(Build.VERSION_CODES.VANILLA_ICE_CREAM)
 public class CertificateTransparencyJob extends BroadcastReceiver {
@@ -37,8 +39,8 @@
     private final Context mContext;
     private final DataStore mDataStore;
     private final CertificateTransparencyDownloader mCertificateTransparencyDownloader;
-    private final CompatibilityVersion mCompatVersion;
     private final SignatureVerifier mSignatureVerifier;
+    private final Collection<CompatibilityVersion> mCompatVersions;
     private final AlarmManager mAlarmManager;
     private final PendingIntent mPendingIntent;
 
@@ -50,13 +52,13 @@
             Context context,
             DataStore dataStore,
             CertificateTransparencyDownloader certificateTransparencyDownloader,
-            CompatibilityVersion compatVersion,
-            SignatureVerifier signatureVerifier) {
+            SignatureVerifier signatureVerifier,
+            Collection<CompatibilityVersion> compatVersions) {
         mContext = context;
         mDataStore = dataStore;
         mCertificateTransparencyDownloader = certificateTransparencyDownloader;
-        mCompatVersion = compatVersion;
         mSignatureVerifier = signatureVerifier;
+        mCompatVersions = compatVersions;
 
         mAlarmManager = context.getSystemService(AlarmManager.class);
         mPendingIntent =
@@ -99,7 +101,9 @@
         }
         mDependenciesReady = false;
 
-        mCompatVersion.delete();
+        for (CompatibilityVersion compatVersion : mCompatVersions) {
+            compatVersion.delete();
+        }
 
         if (Config.DEBUG) {
             Log.d(TAG, "CertificateTransparencyJob canceled.");
@@ -129,7 +133,6 @@
 
     private void startDependencies() {
         mDataStore.load();
-        mCertificateTransparencyDownloader.addCompatibilityVersion(mCompatVersion);
         mSignatureVerifier.loadAllowedKeys();
         mContext.registerReceiver(
                 mCertificateTransparencyDownloader,
@@ -144,7 +147,6 @@
     private void stopDependencies() {
         mContext.unregisterReceiver(mCertificateTransparencyDownloader);
         mSignatureVerifier.clearAllowedKeys();
-        mCertificateTransparencyDownloader.clearCompatibilityVersions();
         mDataStore.delete();
 
         if (Config.DEBUG) {
diff --git a/networksecurity/service/src/com/android/server/net/ct/CertificateTransparencyService.java b/networksecurity/service/src/com/android/server/net/ct/CertificateTransparencyService.java
index 2e910b2..5e530c7 100644
--- a/networksecurity/service/src/com/android/server/net/ct/CertificateTransparencyService.java
+++ b/networksecurity/service/src/com/android/server/net/ct/CertificateTransparencyService.java
@@ -30,6 +30,8 @@
 
 import com.android.server.SystemService;
 
+import java.util.Arrays;
+import java.util.Collection;
 import java.util.concurrent.Executors;
 
 /** Implementation of the Certificate Transparency service. */
@@ -51,8 +53,18 @@
     /** Creates a new {@link CertificateTransparencyService} object. */
     public CertificateTransparencyService(Context context) {
         DataStore dataStore = new DataStore(Config.PREFERENCES_FILE);
-
         SignatureVerifier signatureVerifier = new SignatureVerifier(context);
+        Collection<CompatibilityVersion> compatVersions =
+                Arrays.asList(
+                        new CompatibilityVersion(
+                                Config.COMPATIBILITY_VERSION_V1,
+                                Config.URL_SIGNATURE_V1,
+                                Config.URL_LOG_LIST_V1),
+                        new CompatibilityVersion(
+                                Config.COMPATIBILITY_VERSION_V2,
+                                Config.URL_SIGNATURE_V2,
+                                Config.URL_LOG_LIST_V2));
+
         mCertificateTransparencyJob =
                 new CertificateTransparencyJob(
                         context,
@@ -62,13 +74,10 @@
                                 dataStore,
                                 new DownloadHelper(context),
                                 signatureVerifier,
-                                new CertificateTransparencyLoggerImpl(dataStore)),
-                        new CompatibilityVersion(
-                                Config.COMPATIBILITY_VERSION,
-                                Config.URL_SIGNATURE,
-                                Config.URL_LOG_LIST,
-                                Config.CT_ROOT_DIRECTORY_PATH),
-                        signatureVerifier);
+                                new CertificateTransparencyLoggerImpl(dataStore),
+                                compatVersions),
+                        signatureVerifier,
+                        compatVersions);
     }
 
     /**
diff --git a/networksecurity/service/src/com/android/server/net/ct/CompatibilityVersion.java b/networksecurity/service/src/com/android/server/net/ct/CompatibilityVersion.java
index e8a6e64..0a91963 100644
--- a/networksecurity/service/src/com/android/server/net/ct/CompatibilityVersion.java
+++ b/networksecurity/service/src/com/android/server/net/ct/CompatibilityVersion.java
@@ -23,6 +23,8 @@
 import android.system.Os;
 import android.util.Log;
 
+import androidx.annotation.VisibleForTesting;
+
 import com.android.server.net.ct.CertificateTransparencyLogger.CTLogListUpdateState;
 
 import org.json.JSONException;
@@ -40,6 +42,8 @@
 
     private static final String TAG = "CompatibilityVersion";
 
+    private static File sRootDirectory = new File(Config.CT_ROOT_DIRECTORY_PATH);
+
     static final String LOGS_DIR_PREFIX = "logs-";
     static final String LOGS_LIST_FILE_NAME = "log_list.json";
     static final String CURRENT_LOGS_DIR_SYMLINK_NAME = "current";
@@ -48,23 +52,21 @@
 
     private final String mMetadataUrl;
     private final String mContentUrl;
-    private final File mRootDirectory;
     private final File mVersionDirectory;
     private final File mCurrentLogsDirSymlink;
 
     CompatibilityVersion(
-            String compatVersion, String metadataUrl, String contentUrl, File rootDirectory) {
+            String compatVersion, String metadataUrl, String contentUrl) {
         mCompatVersion = compatVersion;
         mMetadataUrl = metadataUrl;
         mContentUrl = contentUrl;
-        mRootDirectory = rootDirectory;
-        mVersionDirectory = new File(rootDirectory, compatVersion);
+        mVersionDirectory = new File(sRootDirectory, compatVersion);
         mCurrentLogsDirSymlink = new File(mVersionDirectory, CURRENT_LOGS_DIR_SYMLINK_NAME);
     }
 
-    CompatibilityVersion(
-            String compatVersion, String metadataUrl, String contentUrl, String rootDirectoryPath) {
-        this(compatVersion, metadataUrl, contentUrl, new File(rootDirectoryPath));
+    @VisibleForTesting
+    static void setRootDirectoryForTesting(File rootDirectory) {
+        sRootDirectory = rootDirectory;
     }
 
     /**
@@ -75,8 +77,8 @@
      * @return true if the log list was installed successfully, false otherwise.
      * @throws IOException if the list cannot be saved in the CT directory.
      */
-    LogListUpdateStatus install(
-            InputStream newContent, LogListUpdateStatus.Builder statusBuilder) throws IOException {
+    LogListUpdateStatus install(InputStream newContent, LogListUpdateStatus.Builder statusBuilder)
+            throws IOException {
         String content = new String(newContent.readAllBytes(), UTF_8);
         try {
             JSONObject contentJson = new JSONObject(content);
@@ -98,7 +100,7 @@
         // there's a bunch of steps. We create a new directory with the logs and then do
         // an atomic update of the current symlink to point to the new directory.
         // 1. Ensure the path to the root and version directories exist and are readable.
-        DirectoryUtils.makeDir(mRootDirectory);
+        DirectoryUtils.makeDir(sRootDirectory);
         DirectoryUtils.makeDir(mVersionDirectory);
 
         File newLogsDir = new File(mVersionDirectory, LOGS_DIR_PREFIX + version);
diff --git a/networksecurity/service/src/com/android/server/net/ct/Config.java b/networksecurity/service/src/com/android/server/net/ct/Config.java
index 5fdba09..72b715a 100644
--- a/networksecurity/service/src/com/android/server/net/ct/Config.java
+++ b/networksecurity/service/src/com/android/server/net/ct/Config.java
@@ -33,18 +33,14 @@
     private static final String PREFERENCES_FILE_NAME = "ct.preferences";
     static final File PREFERENCES_FILE = new File(DEVICE_PROTECTED_DATA_DIR, PREFERENCES_FILE_NAME);
 
-    // CT directory
+    // CT paths
     static final String CT_ROOT_DIRECTORY_PATH = "/data/misc/keychain/ct/";
-    static final String COMPATIBILITY_VERSION = "v1";
+    static final String URL_PREFIX = "https://www.gstatic.com/android/certificate_transparency/";
 
     // Phenotype flags
     static final String NAMESPACE_NETWORK_SECURITY = "network_security";
     private static final String FLAGS_PREFIX = "CertificateTransparencyLogList__";
     static final String FLAG_SERVICE_ENABLED = FLAGS_PREFIX + "service_enabled";
-    static final String FLAG_CONTENT_URL = FLAGS_PREFIX + "content_url";
-    static final String FLAG_METADATA_URL = FLAGS_PREFIX + "metadata_url";
-    static final String FLAG_VERSION = FLAGS_PREFIX + "version";
-    static final String FLAG_PUBLIC_KEY = FLAGS_PREFIX + "public_key";
 
     // properties
     static final String VERSION = "version";
@@ -53,9 +49,18 @@
     static final String PUBLIC_KEY_DOWNLOAD_ID = "public_key_download_id";
     static final String LOG_LIST_UPDATE_FAILURE_COUNT = "log_list_update_failure_count";
 
-    // URLs
-    static final String URL_PREFIX = "https://www.gstatic.com/android/certificate_transparency/";
-    static final String URL_LOG_LIST = URL_PREFIX + "log_list.json";
-    static final String URL_SIGNATURE = URL_PREFIX + "log_list.sig";
+    // Public Key URLs
     static final String URL_PUBLIC_KEY = URL_PREFIX + "log_list.pub";
+
+    // Compatibility Version v1
+    static final String COMPATIBILITY_VERSION_V1 = "v1";
+    static final String URL_PREFIX_V1 = URL_PREFIX;
+    static final String URL_LOG_LIST_V1 = URL_PREFIX_V1 + "log_list.json";
+    static final String URL_SIGNATURE_V1 = URL_PREFIX_V1 + "log_list.sig";
+
+    // Compatibility Version v2
+    static final String COMPATIBILITY_VERSION_V2 = "v2";
+    static final String URL_PREFIX_V2 = URL_PREFIX + COMPATIBILITY_VERSION_V2 + "/";
+    static final String URL_LOG_LIST_V2 = URL_PREFIX_V2 + "log_list.json";
+    static final String URL_SIGNATURE_V2 = URL_PREFIX_V2 + "log_list.sig";
 }
diff --git a/networksecurity/tests/unit/src/com/android/server/net/ct/CertificateTransparencyDownloaderTest.java b/networksecurity/tests/unit/src/com/android/server/net/ct/CertificateTransparencyDownloaderTest.java
index 22dc6ab..956bad5 100644
--- a/networksecurity/tests/unit/src/com/android/server/net/ct/CertificateTransparencyDownloaderTest.java
+++ b/networksecurity/tests/unit/src/com/android/server/net/ct/CertificateTransparencyDownloaderTest.java
@@ -60,6 +60,7 @@
 import java.security.PrivateKey;
 import java.security.PublicKey;
 import java.security.Signature;
+import java.util.Arrays;
 import java.util.Base64;
 import java.util.Optional;
 
@@ -94,24 +95,25 @@
         mContext = InstrumentationRegistry.getInstrumentation().getContext();
         mDataStore = new DataStore(File.createTempFile("datastore-test", ".properties"));
         mSignatureVerifier = new SignatureVerifier(mContext);
+
+        CompatibilityVersion.setRootDirectoryForTesting(mContext.getFilesDir());
+        mCompatVersion =
+                new CompatibilityVersion(
+                        /* compatVersion= */ "v666",
+                        Config.URL_SIGNATURE_V1,
+                        Config.URL_LOG_LIST_V1);
         mCertificateTransparencyDownloader =
                 new CertificateTransparencyDownloader(
                         mContext,
                         mDataStore,
                         new DownloadHelper(mDownloadManager),
                         mSignatureVerifier,
-                        mLogger);
-        mCompatVersion =
-                new CompatibilityVersion(
-                        /* compatVersion= */ "v666",
-                        Config.URL_SIGNATURE,
-                        Config.URL_LOG_LIST,
-                        mContext.getFilesDir());
+                        mLogger,
+                        Arrays.asList(mCompatVersion));
 
         prepareDownloadManager();
         mSignatureVerifier.addAllowedKey(mPublicKey);
         mDataStore.load();
-        mCertificateTransparencyDownloader.addCompatibilityVersion(mCompatVersion);
     }
 
     @After
diff --git a/networksecurity/tests/unit/src/com/android/server/net/ct/CompatibilityVersionTest.java b/networksecurity/tests/unit/src/com/android/server/net/ct/CompatibilityVersionTest.java
index 2b8b3cd..0d15183 100644
--- a/networksecurity/tests/unit/src/com/android/server/net/ct/CompatibilityVersionTest.java
+++ b/networksecurity/tests/unit/src/com/android/server/net/ct/CompatibilityVersionTest.java
@@ -27,6 +27,7 @@
 import org.json.JSONException;
 import org.json.JSONObject;
 import org.junit.After;
+import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.JUnit4;
@@ -47,9 +48,16 @@
 
     private final File mTestDir =
             InstrumentationRegistry.getInstrumentation().getContext().getFilesDir();
-    private final CompatibilityVersion mCompatVersion =
-            new CompatibilityVersion(
-                    TEST_VERSION, Config.URL_SIGNATURE, Config.URL_LOG_LIST, mTestDir);
+
+    private CompatibilityVersion mCompatVersion;
+
+    @Before
+    public void setUp() {
+        CompatibilityVersion.setRootDirectoryForTesting(mTestDir);
+        mCompatVersion =
+                new CompatibilityVersion(
+                        TEST_VERSION, Config.URL_SIGNATURE_V1, Config.URL_LOG_LIST_V1);
+    }
 
     @After
     public void tearDown() {
@@ -111,9 +119,7 @@
         JSONObject logList = makeLogList(version, "i_am_content");
 
         try (InputStream inputStream = asStream(logList)) {
-            assertThat(
-                            mCompatVersion.install(
-                                    inputStream, LogListUpdateStatus.builder()))
+            assertThat(mCompatVersion.install(inputStream, LogListUpdateStatus.builder()))
                     .isEqualTo(getSuccessfulUpdateStatus());
         }
 
@@ -142,9 +148,7 @@
     @Test
     public void testCompatibilityVersion_deleteSuccessfully() throws Exception {
         try (InputStream inputStream = asStream(makeLogList(/* version= */ "123"))) {
-            assertThat(
-                            mCompatVersion.install(
-                                    inputStream, LogListUpdateStatus.builder()))
+            assertThat(mCompatVersion.install(inputStream, LogListUpdateStatus.builder()))
                     .isEqualTo(getSuccessfulUpdateStatus());
         }
 
@@ -156,9 +160,7 @@
     @Test
     public void testCompatibilityVersion_invalidLogList() throws Exception {
         try (InputStream inputStream = new ByteArrayInputStream(("not_a_valid_list".getBytes()))) {
-            assertThat(
-                            mCompatVersion.install(
-                                    inputStream, LogListUpdateStatus.builder()))
+            assertThat(mCompatVersion.install(inputStream, LogListUpdateStatus.builder()))
                     .isEqualTo(LogListUpdateStatus.builder().setState(LOG_LIST_INVALID).build());
         }
 
@@ -179,9 +181,7 @@
 
         JSONObject newLogList = makeLogList(existingVersion, "i_am_the_real_content");
         try (InputStream inputStream = asStream(newLogList)) {
-            assertThat(
-                            mCompatVersion.install(
-                                    inputStream, LogListUpdateStatus.builder()))
+            assertThat(mCompatVersion.install(inputStream, LogListUpdateStatus.builder()))
                     .isEqualTo(getSuccessfulUpdateStatus());
         }
 
@@ -193,16 +193,12 @@
         String existingVersion = "666";
         JSONObject existingLogList = makeLogList(existingVersion, "i_was_installed_successfully");
         try (InputStream inputStream = asStream(existingLogList)) {
-            assertThat(
-                            mCompatVersion.install(
-                                    inputStream, LogListUpdateStatus.builder()))
+            assertThat(mCompatVersion.install(inputStream, LogListUpdateStatus.builder()))
                     .isEqualTo(getSuccessfulUpdateStatus());
         }
 
         try (InputStream inputStream = asStream(makeLogList(existingVersion, "i_am_ignored"))) {
-            assertThat(
-                            mCompatVersion.install(
-                                    inputStream, LogListUpdateStatus.builder()))
+            assertThat(mCompatVersion.install(inputStream, LogListUpdateStatus.builder()))
                     .isEqualTo(
                             LogListUpdateStatus.builder()
                                     .setState(VERSION_ALREADY_EXISTS)