diff --git a/nearby/service/Android.bp b/nearby/service/Android.bp
index 6743c21..12fce04 100644
--- a/nearby/service/Android.bp
+++ b/nearby/service/Android.bp
@@ -67,6 +67,7 @@
         "modules-utils-handlerexecutor",
         "modules-utils-preconditions",
         "modules-utils-backgroundthread",
+        "presence-lite-protos",
     ],
     sdk_version: "system_server_current",
     // This is included in service-connectivity which is 30+
diff --git a/nearby/service/java/com/android/server/nearby/NearbyService.java b/nearby/service/java/com/android/server/nearby/NearbyService.java
index 5326673..6d149fc 100644
--- a/nearby/service/java/com/android/server/nearby/NearbyService.java
+++ b/nearby/service/java/com/android/server/nearby/NearbyService.java
@@ -26,6 +26,7 @@
 import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
+import android.hardware.location.ContextHubManager;
 import android.nearby.INearbyManager;
 import android.nearby.IScanListener;
 import android.nearby.ScanRequest;
@@ -33,34 +34,42 @@
 
 import com.android.server.nearby.common.locator.LocatorContextWrapper;
 import com.android.server.nearby.fastpair.FastPairManager;
+import com.android.server.nearby.injector.ContextHubManagerAdapter;
 import com.android.server.nearby.injector.Injector;
+import com.android.server.nearby.presence.ChreCommunication;
+import com.android.server.nearby.presence.PresenceManager;
 import com.android.server.nearby.provider.DiscoveryProviderManager;
 import com.android.server.nearby.provider.FastPairDataProvider;
 
-/**
- * Service implementing nearby functionality.
- */
+import java.util.concurrent.Executors;
+
+import service.proto.Blefilter;
+
+/** Service implementing nearby functionality. */
 public class NearbyService extends INearbyManager.Stub {
     public static final String TAG = "NearbyService";
 
     private final Context mContext;
     private final SystemInjector mSystemInjector;
     private final FastPairManager mFastPairManager;
-    private final BroadcastReceiver mBluetoothReceiver = new BroadcastReceiver() {
-        @Override
-        public void onReceive(Context context, Intent intent) {
-            int state = intent
-                    .getIntExtra(BluetoothAdapter.EXTRA_STATE, BluetoothAdapter.ERROR);
-            if (state == BluetoothAdapter.STATE_ON) {
-                if (mSystemInjector != null) {
-                    // Have to do this logic in listener. Even during PHASE_BOOT_COMPLETED
-                    // phase, BluetoothAdapter is not null, the BleScanner is null.
-                    Log.v(TAG, "Initiating BluetoothAdapter when Bluetooth is turned on.");
-                    mSystemInjector.initializeBluetoothAdapter();
+    private final PresenceManager mPresenceManager;
+    private final BroadcastReceiver mBluetoothReceiver =
+            new BroadcastReceiver() {
+                @Override
+                public void onReceive(Context context, Intent intent) {
+                    int state =
+                            intent.getIntExtra(
+                                    BluetoothAdapter.EXTRA_STATE, BluetoothAdapter.ERROR);
+                    if (state == BluetoothAdapter.STATE_ON) {
+                        if (mSystemInjector != null) {
+                            // Have to do this logic in listener. Even during PHASE_BOOT_COMPLETED
+                            // phase, BluetoothAdapter is not null, the BleScanner is null.
+                            Log.v(TAG, "Initiating BluetoothAdapter when Bluetooth is turned on.");
+                            mSystemInjector.initializeBluetoothAdapter();
+                        }
+                    }
                 }
-            }
-        }
-    };
+            };
     private DiscoveryProviderManager mProviderManager;
 
     public NearbyService(Context context) {
@@ -69,6 +78,19 @@
         mProviderManager = new DiscoveryProviderManager(context, mSystemInjector);
         final LocatorContextWrapper lcw = new LocatorContextWrapper(context, null);
         mFastPairManager = new FastPairManager(lcw);
+        mPresenceManager =
+                new PresenceManager(
+                        mContext,
+                        (results) -> {
+                            // TODO(b/221082271): hooked with API codes.
+                            for (Blefilter.BleFilterResult result : results.getResultList()) {
+                                Log.i(
+                                        TAG,
+                                        String.format(
+                                                "received filter result with id: %d",
+                                                result.getId()));
+                            }
+                        });
     }
 
     @Override
@@ -84,7 +106,7 @@
     /**
      * Called by the service initializer.
      *
-     * {@see com.android.server.SystemService#onBootPhase}.
+     * <p>{@see com.android.server.SystemService#onBootPhase}.
      */
     public void onBootPhase(int phase) {
         switch (phase) {
@@ -95,17 +117,22 @@
             case PHASE_BOOT_COMPLETED:
                 // The nearby service must be functioning after this boot phase.
                 mSystemInjector.initializeBluetoothAdapter();
-                mContext.registerReceiver(mBluetoothReceiver,
+                mContext.registerReceiver(
+                        mBluetoothReceiver,
                         new IntentFilter(BluetoothAdapter.ACTION_STATE_CHANGED));
                 mFastPairManager.initiate();
+                mSystemInjector.initializeContextHubManagerAdapter();
+                mPresenceManager.initiate(
+                        new ChreCommunication(
+                                mSystemInjector, Executors.newSingleThreadExecutor()));
                 break;
         }
     }
 
     private static final class SystemInjector implements Injector {
         private final Context mContext;
-        @Nullable
-        private BluetoothAdapter mBluetoothAdapter;
+        @Nullable private BluetoothAdapter mBluetoothAdapter;
+        @Nullable private  ContextHubManagerAdapter mContextHubManagerAdapter;
 
         SystemInjector(Context context) {
             mContext = context;
@@ -117,6 +144,11 @@
             return mBluetoothAdapter;
         }
 
+        @Override
+        public ContextHubManagerAdapter getContextHubManagerAdapter() {
+            return mContextHubManagerAdapter;
+        }
+
         synchronized void initializeBluetoothAdapter() {
             if (mBluetoothAdapter != null) {
                 return;
@@ -127,6 +159,17 @@
             }
             mBluetoothAdapter = manager.getAdapter();
         }
-    }
 
+        synchronized void initializeContextHubManagerAdapter() {
+            if (mContextHubManagerAdapter != null) {
+                return;
+            }
+            ContextHubManager manager = mContext.getSystemService(ContextHubManager.class);
+            if (manager == null) {
+                return;
+            }
+            mContextHubManagerAdapter = new ContextHubManagerAdapter(manager);
+        }
+
+    }
 }
diff --git a/nearby/service/java/com/android/server/nearby/injector/ContextHubManagerAdapter.java b/nearby/service/java/com/android/server/nearby/injector/ContextHubManagerAdapter.java
new file mode 100644
index 0000000..9af0227
--- /dev/null
+++ b/nearby/service/java/com/android/server/nearby/injector/ContextHubManagerAdapter.java
@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * 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 com.android.server.nearby.injector;
+
+import android.hardware.location.ContextHubClient;
+import android.hardware.location.ContextHubClientCallback;
+import android.hardware.location.ContextHubInfo;
+import android.hardware.location.ContextHubManager;
+import android.hardware.location.ContextHubTransaction;
+import android.hardware.location.NanoAppState;
+
+import java.util.List;
+import java.util.concurrent.Executor;
+
+/** Wrap {@link ContextHubManager} for dependence injection. */
+public class ContextHubManagerAdapter {
+    private final ContextHubManager mManager;
+
+    public ContextHubManagerAdapter(ContextHubManager manager) {
+        mManager = manager;
+    }
+
+    /**
+     * Returns the list of ContextHubInfo objects describing the available Context Hubs.
+     *
+     * @return the list of ContextHubInfo objects
+     * @see ContextHubInfo
+     */
+    public List<ContextHubInfo> getContextHubs() {
+        return mManager.getContextHubs();
+    }
+
+    /**
+     * Requests a query for nanoapps loaded at the specified Context Hub.
+     *
+     * @param hubInfo the hub to query a list of nanoapps from
+     * @return the ContextHubTransaction of the request
+     * @throws NullPointerException if hubInfo is null
+     */
+    public ContextHubTransaction<List<NanoAppState>> queryNanoApps(ContextHubInfo hubInfo) {
+        return mManager.queryNanoApps(hubInfo);
+    }
+
+    /**
+     * Creates and registers a client and its callback with the Context Hub Service.
+     *
+     * <p>A client is registered with the Context Hub Service for a specified Context Hub. When the
+     * registration succeeds, the client can send messages to nanoapps through the returned {@link
+     * ContextHubClient} object, and receive notifications through the provided callback.
+     *
+     * @param hubInfo the hub to attach this client to
+     * @param executor the executor to invoke the callback
+     * @param callback the notification callback to register
+     * @return the registered client object
+     * @throws IllegalArgumentException if hubInfo does not represent a valid hub
+     * @throws IllegalStateException if there were too many registered clients at the service
+     * @throws NullPointerException if callback, hubInfo, or executor is null
+     */
+    public ContextHubClient createClient(
+            ContextHubInfo hubInfo, ContextHubClientCallback callback, Executor executor) {
+        return mManager.createClient(hubInfo, callback, executor);
+    }
+}
diff --git a/nearby/service/java/com/android/server/nearby/injector/Injector.java b/nearby/service/java/com/android/server/nearby/injector/Injector.java
index d221722..f990dc9 100644
--- a/nearby/service/java/com/android/server/nearby/injector/Injector.java
+++ b/nearby/service/java/com/android/server/nearby/injector/Injector.java
@@ -19,14 +19,14 @@
 import android.bluetooth.BluetoothAdapter;
 
 /**
- *  Nearby dependency injector. To be used for accessing various Nearby class instances and as a
- *  handle for mock injection.
+ * Nearby dependency injector. To be used for accessing various Nearby class instances and as a
+ * handle for mock injection.
  */
 public interface Injector {
 
-    /**
-     * Get the BluetoothAdapter for BleDiscoveryProvider to scan.
-     */
+    /** Get the BluetoothAdapter for BleDiscoveryProvider to scan. */
     BluetoothAdapter getBluetoothAdapter();
 
+    /** Get the ContextHubManagerAdapter for ChreDiscoveryProvider to scan. */
+    ContextHubManagerAdapter getContextHubManagerAdapter();
 }
diff --git a/nearby/service/java/com/android/server/nearby/presence/ChreCommunication.java b/nearby/service/java/com/android/server/nearby/presence/ChreCommunication.java
new file mode 100644
index 0000000..fc9863e
--- /dev/null
+++ b/nearby/service/java/com/android/server/nearby/presence/ChreCommunication.java
@@ -0,0 +1,261 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * 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 com.android.server.nearby.presence;
+
+import android.annotation.Nullable;
+import android.hardware.location.ContextHubClient;
+import android.hardware.location.ContextHubClientCallback;
+import android.hardware.location.ContextHubInfo;
+import android.hardware.location.ContextHubTransaction;
+import android.hardware.location.NanoAppMessage;
+import android.hardware.location.NanoAppState;
+import android.util.Log;
+
+import com.android.server.nearby.injector.ContextHubManagerAdapter;
+import com.android.server.nearby.injector.Injector;
+
+import com.google.common.base.Preconditions;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Locale;
+import java.util.Set;
+import java.util.concurrent.Executor;
+
+/**
+ * Responsible for setting up communication with the appropriate contexthub on the device and
+ * handling nanoapp messages to / from it.
+ */
+public class ChreCommunication extends ContextHubClientCallback {
+
+    /** Callback that receives messages forwarded from the context hub. */
+    public interface ContextHubCommsCallback {
+        /** Indicates whether {@link ChreCommunication} was started successfully. */
+        void started(boolean success);
+
+        /** Indicates the ContextHub has been restarted. */
+        void onHubReset();
+
+        /**
+         * Indicates the given {@code nanoAppId} has been restarted. Either via code download or by
+         * being enabled by CHRE.
+         */
+        void onNanoAppRestart(long nanoAppId);
+
+        /** Indicates a new {@link NanoAppMessage} has been received. */
+        void onMessageFromNanoApp(NanoAppMessage message);
+    }
+
+    public static final String TAG = "PresenceService";
+    @Nullable private final ContextHubManagerAdapter mManager;
+    private final Executor mExecutor;
+
+    private boolean mStarted = false;
+    @Nullable private ContextHubCommsCallback mCallback;
+    @Nullable private ContextHubClient mContextHubClient;
+
+    public ChreCommunication(Injector injector, Executor executor) {
+        this.mManager = injector.getContextHubManagerAdapter();
+        mExecutor = executor;
+    }
+
+    /**
+     * Starts communication with the contexthub. This will invoke {@link
+     * ContextHubCommsCallback#start(boolean)} on completion.
+     *
+     * @param nanoAppIds - List of IDs that must have at least one match inside the chosen
+     *     contexthub.
+     */
+    public synchronized void start(ContextHubCommsCallback callback, Set<Long> nanoAppIds) {
+        if (this.mManager == null) {
+            Log.e(TAG, "ContexHub not available in this device");
+            return;
+        } else {
+            Log.i(TAG, "Start ChreCommunication");
+        }
+        Preconditions.checkNotNull(callback);
+        if (nanoAppIds.isEmpty() || mManager == null) {
+            callback.started(false);
+            return;
+        }
+        if (mStarted) {
+            this.mCallback.started(true);
+            return;
+        }
+
+        // Use this to indicate whether stop was called before the transaction below
+        // completes.
+        mStarted = true;
+        this.mCallback = callback;
+
+        List<ContextHubInfo> contextHubs = mManager.getContextHubs();
+
+        // Make a copy of the list so we can modify it during our async callbacks (in case the code
+        // is still iterating)
+        List<ContextHubInfo> validContextHubs = new ArrayList<>(contextHubs);
+
+        for (ContextHubInfo info : contextHubs) {
+            ContextHubTransaction<List<NanoAppState>> transaction = mManager.queryNanoApps(info);
+            Log.i(TAG, "After query Nano Apps ");
+            transaction.setOnCompleteListener(
+                    new OnQueryCompleteListener(info, validContextHubs, nanoAppIds), mExecutor);
+        }
+    }
+
+    /**
+     * Closes the connection to the {@link ContextHub} chosen during start.
+     *
+     * <p>NOTE: Do not invoke any other methods on this class after this returns.
+     */
+    public synchronized void stop() {
+        if (!mStarted) {
+            return;
+        }
+        mStarted = false;
+        if (mContextHubClient != null) {
+            mContextHubClient.close();
+            mContextHubClient = null;
+        }
+    }
+
+    /** Sends a {@link NanoAppMessage} to Context Hub Nearby nanoapp. */
+    public synchronized boolean sendMessageToNanoApp(NanoAppMessage message) {
+        if (mContextHubClient == null) {
+            Log.i(TAG, "Error sending message to nanoapp, contextHubClient is null");
+            return false;
+        }
+        int result = mContextHubClient.sendMessageToNanoApp(message);
+        if (result != ContextHubTransaction.RESULT_SUCCESS) {
+            Log.i(
+                    TAG,
+                    String.format(
+                            Locale.getDefault(),
+                            "Error sending message to nanoapp: %s",
+                            contextHubTransactionResultToString(result)));
+            return false;
+        }
+        return true;
+    }
+
+    @Override
+    public synchronized void onMessageFromNanoApp(ContextHubClient client, NanoAppMessage message) {
+        mCallback.onMessageFromNanoApp(message);
+    }
+
+    @Override
+    public synchronized void onHubReset(ContextHubClient client) {
+        mCallback.onHubReset();
+    }
+
+    @Override
+    public synchronized void onNanoAppLoaded(ContextHubClient client, long nanoAppId) {
+        Log.i(TAG, String.format("Nanoapp ID loaded: %s", nanoAppId));
+        mCallback.onNanoAppRestart(nanoAppId);
+    }
+
+    private static String contextHubTransactionResultToString(int result) {
+        switch (result) {
+            case ContextHubTransaction.RESULT_SUCCESS:
+                return "RESULT_SUCCESS";
+            case ContextHubTransaction.RESULT_FAILED_UNKNOWN:
+                return "RESULT_FAILED_UNKNOWN";
+            case ContextHubTransaction.RESULT_FAILED_BAD_PARAMS:
+                return "RESULT_FAILED_BAD_PARAMS";
+            case ContextHubTransaction.RESULT_FAILED_UNINITIALIZED:
+                return "RESULT_FAILED_UNINITIALIZED";
+            case ContextHubTransaction.RESULT_FAILED_BUSY:
+                return "RESULT_FAILED_BUSY";
+            case ContextHubTransaction.RESULT_FAILED_AT_HUB:
+                return "RESULT_FAILED_AT_HUB";
+            case ContextHubTransaction.RESULT_FAILED_TIMEOUT:
+                return "RESULT_FAILED_TIMEOUT";
+            case ContextHubTransaction.RESULT_FAILED_SERVICE_INTERNAL_FAILURE:
+                return "RESULT_FAILED_SERVICE_INTERNAL_FAILURE";
+            case ContextHubTransaction.RESULT_FAILED_HAL_UNAVAILABLE:
+                return "RESULT_FAILED_HAL_UNAVAILABLE";
+            default:
+                return String.format(Locale.getDefault(), "UNKNOWN_RESULT value=%d", result);
+        }
+    }
+
+    /**
+     * Used when initializing the class to identify the appropriate {@link ContextHubInfo} to listen
+     * to.
+     */
+    class OnQueryCompleteListener
+            implements ContextHubTransaction.OnCompleteListener<List<NanoAppState>> {
+
+        private final ContextHubInfo mQueriedContextHub;
+        private final List<ContextHubInfo> mContextHubs;
+        private final Set<Long> mNanoAppIds;
+
+        OnQueryCompleteListener(
+                ContextHubInfo queriedContextHub,
+                List<ContextHubInfo> contextHubs,
+                Set<Long> nanoAppIds) {
+            this.mQueriedContextHub = queriedContextHub;
+            this.mContextHubs = contextHubs;
+            this.mNanoAppIds = nanoAppIds;
+        }
+
+        @Override
+        public void onComplete(
+                ContextHubTransaction<List<NanoAppState>> transaction,
+                ContextHubTransaction.Response<List<NanoAppState>> response) {
+            Log.i(TAG, "query nano app onComplete");
+            // Ensure the class hasn't found a client already or stop hasn't been called before
+            // the transaction completed to avoid messing with state.
+            if (mContextHubClient != null || !mStarted) {
+                return;
+            }
+
+            if (response.getResult() == ContextHubTransaction.RESULT_SUCCESS) {
+                for (NanoAppState state : response.getContents()) {
+                    if (mNanoAppIds.contains(state.getNanoAppId())) {
+                        Log.i(
+                                TAG,
+                                String.format(
+                                        "Found valid contexthub: %s", mQueriedContextHub.getId()));
+                        mContextHubClient =
+                                mManager.createClient(
+                                        mQueriedContextHub, ChreCommunication.this, mExecutor);
+                        mCallback.started(true);
+                        return;
+                    }
+                }
+                Log.e(
+                        TAG,
+                        String.format(
+                                "Didn't find the nanoapp on contexthub: %s",
+                                mQueriedContextHub.getId()));
+            } else {
+                Log.e(
+                        TAG,
+                        String.format(
+                                "Failed to communicate with contexthub: %s",
+                                mQueriedContextHub.getId()));
+            }
+
+            mContextHubs.remove(mQueriedContextHub);
+            // If this is the last context hub response left to receive, indicate that
+            // there isn't a valid context available on this device.
+            if (mContextHubs.isEmpty()) {
+                mCallback.started(false);
+            }
+        }
+    }
+}
diff --git a/nearby/service/java/com/android/server/nearby/presence/PresenceManager.java b/nearby/service/java/com/android/server/nearby/presence/PresenceManager.java
new file mode 100644
index 0000000..66d4864
--- /dev/null
+++ b/nearby/service/java/com/android/server/nearby/presence/PresenceManager.java
@@ -0,0 +1,167 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * 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 com.android.server.nearby.presence;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.hardware.location.NanoAppMessage;
+import android.util.Log;
+
+import com.android.internal.annotations.VisibleForTesting;
+
+import com.google.protobuf.ByteString;
+import com.google.protobuf.InvalidProtocolBufferException;
+
+import java.util.Collections;
+
+import service.proto.Blefilter;
+
+/** PresenceManager is the class initiated in nearby service to handle presence related work. */
+public class PresenceManager {
+    /** Callback that receives filter results from CHRE Nanoapp. */
+    public interface PresenceCallback {
+        /** Called when {@link BleFilterResults} has been received. */
+        void onFilterResults(Blefilter.BleFilterResults filterResults);
+    }
+
+    private static final String TAG = "PresenceService";
+    // Nanoapp ID reserved for Nearby Presence.
+    /** @hide */
+    @VisibleForTesting
+    public static final long NANOAPP_ID = 0x476f6f676c001031L;
+    /** @hide */
+    @VisibleForTesting
+    public static final int NANOAPP_MESSAGE_TYPE_FILTER = 3;
+    /** @hide */
+    @VisibleForTesting
+    public static final int NANOAPP_MESSAGE_TYPE_FILTER_RESULT = 4;
+    private final Context mContext;
+    private final PresenceCallback mPresenceCallback;
+    private final ChreCallback mChreCallback;
+    private ChreCommunication mChreCommunication;
+
+    private Blefilter.BleFilters mFilters = null;
+    private boolean mChreStarted = false;
+
+    private final IntentFilter mIntentFilter;
+
+    private final BroadcastReceiver mScreenBroadcastReceiver =
+            new BroadcastReceiver() {
+                @Override
+                public void onReceive(Context context, Intent intent) {
+                    if (intent.getAction().equals(Intent.ACTION_SCREEN_ON)) {
+                        // TODO(b/221082271): removed this faked data once hooked with API codes.
+                        Log.d(TAG, "Update Presence CHRE filter");
+                        ByteString mac_addr = ByteString.copyFrom(new byte[] {1, 2, 3, 4, 5, 6});
+                        Blefilter.BleFilter filter =
+                                Blefilter.BleFilter.newBuilder()
+                                        .setId(0)
+                                        .setUuid(0xFCF1)
+                                        .setIntent(1)
+                                        .setMacAddress(mac_addr)
+                                        .build();
+                        Blefilter.BleFilters filters =
+                                Blefilter.BleFilters.newBuilder().addFilter(filter).build();
+                        updateFilters(filters);
+                    }
+                }
+            };
+
+    public PresenceManager(Context context, PresenceCallback presenceCallback) {
+        mContext = context;
+        mPresenceCallback = presenceCallback;
+        mChreCallback = new ChreCallback();
+        mIntentFilter = new IntentFilter();
+    }
+
+    /** Function called when nearby service start. */
+    public void initiate(ChreCommunication chreCommunication) {
+        mChreCommunication = chreCommunication;
+        mChreCommunication.start(mChreCallback, Collections.singleton(NANOAPP_ID));
+
+        mIntentFilter.addAction(Intent.ACTION_SCREEN_ON);
+        mContext.registerReceiver(mScreenBroadcastReceiver, mIntentFilter);
+    }
+
+    /** Updates the fitlers in Context Hub. */
+    public synchronized void updateFilters(Blefilter.BleFilters filters) {
+        mFilters = filters;
+        if (mChreStarted) {
+            sendFilters(mFilters);
+            mFilters = null;
+        }
+    }
+
+    private void sendFilters(Blefilter.BleFilters filters) {
+        NanoAppMessage message =
+                NanoAppMessage.createMessageToNanoApp(
+                        NANOAPP_ID, NANOAPP_MESSAGE_TYPE_FILTER, filters.toByteArray());
+        if (!mChreCommunication.sendMessageToNanoApp(message)) {
+            Log.e(TAG, "Failed to send filters to CHRE.");
+        }
+    }
+
+    private class ChreCallback implements ChreCommunication.ContextHubCommsCallback {
+
+        @Override
+        public void started(boolean success) {
+            if (success) {
+                synchronized (PresenceManager.this) {
+                    Log.i(TAG, "CHRE communication started");
+                    mChreStarted = true;
+                    if (mFilters != null) {
+                        sendFilters(mFilters);
+                        mFilters = null;
+                    }
+                }
+            }
+        }
+
+        @Override
+        public void onHubReset() {
+            // TODO(b/221082271): hooked with upper level codes.
+            Log.i(TAG, "CHRE reset.");
+        }
+
+        @Override
+        public void onNanoAppRestart(long nanoAppId) {
+            // TODO(b/221082271): hooked with upper level codes.
+            Log.i(TAG, String.format("CHRE NanoApp %d restart.", nanoAppId));
+        }
+
+        @Override
+        public void onMessageFromNanoApp(NanoAppMessage message) {
+            if (message.getNanoAppId() != NANOAPP_ID) {
+                Log.e(TAG, "Received message from unknown nano app.");
+                return;
+            }
+            if (message.getMessageType() == NANOAPP_MESSAGE_TYPE_FILTER_RESULT) {
+                try {
+                    Blefilter.BleFilterResults results =
+                            Blefilter.BleFilterResults.parseFrom(message.getMessageBody());
+                    mPresenceCallback.onFilterResults(results);
+                } catch (InvalidProtocolBufferException e) {
+                    Log.e(
+                            TAG,
+                            String.format("Failed to decode the filter result %s", e.toString()));
+                }
+            }
+        }
+    }
+}
diff --git a/nearby/service/proto/Android.bp b/nearby/service/proto/Android.bp
index d8c059e..1b00cf6 100644
--- a/nearby/service/proto/Android.bp
+++ b/nearby/service/proto/Android.bp
@@ -23,10 +23,22 @@
     },
     sdk_version: "system_current",
     min_sdk_version: "30",
-    srcs: ["src/*/*.proto"],
+    srcs: ["src/fastpair/*.proto"],
     apex_available: [
         "com.android.tethering",
     ],
 }
 
-
+java_library {
+    name: "presence-lite-protos",
+    proto: {
+        type: "lite",
+        canonical_path_from_root: false,
+    },
+    sdk_version: "system_current",
+    min_sdk_version: "30",
+    srcs: ["src/presence/*.proto"],
+    apex_available: [
+        "com.android.tethering",
+    ],
+}
\ No newline at end of file
diff --git a/nearby/service/proto/src/presence/blefilter.proto b/nearby/service/proto/src/presence/blefilter.proto
new file mode 100644
index 0000000..da56522
--- /dev/null
+++ b/nearby/service/proto/src/presence/blefilter.proto
@@ -0,0 +1,82 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * 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.
+ */
+
+// Proto Messages define the interface between Nearby nanoapp and its host.
+//
+// Host registers its interest in BLE event by configuring nanoapp with Filters.
+// The nanoapp keeps watching BLE events and notifies host once an event matches
+// a Filter.
+//
+// Each Filter is defined by its id (required) with optional fields of rssi,
+// uuid, MAC etc. The host should guarantee the uniqueness of ids. It is
+// convenient to assign id incrementally when adding a Filter such that its id
+// is the same as the index of the repeated field in Filters.
+//
+// The nanoapp compares each BLE event against the list of Filters, and notifies
+// host when the event matches a Filter. The Field's id will be sent back to
+// host in the FilterResult.
+//
+// It is possible for the nanoapp to return multiple ids when an event matches
+// multiple Filters.
+
+syntax = "proto2";
+
+package service.proto;
+
+// Certificate to verify BLE events from trusted devices.
+// When receiving an advertisement from a remote device, it will
+// be decrypted by authenticity_key and SHA hashed. The device
+// is verified as trusted if the hash result is equal to
+// metadata_encryption_key_tag.
+// See details in go/ns-certificates.
+message PublicateCertificate {
+  optional bytes authenticity_key = 1;
+  optional bytes metadata_encryption_key_tag = 2;
+}
+
+message BleFilter {
+  optional uint32 id = 1;  // Required, unique id of this filter.
+  // Maximum delay to notify the client after an event occurs.
+  optional uint32 latency_ms = 2;
+  optional uint32 uuid = 3;
+  // MAC address of the advertising device.
+  optional bytes mac_address = 4;
+  optional bytes mac_mask = 5;
+  // Represents an action that scanners should take when they receive this
+  // packet. See go/nearby-presence-spec for details.
+  optional uint32 intent = 6;
+  // Notify the client if the advertising device is within the distance.
+  // For moving object, the distance is averaged over data sampled within
+  // the period of latency defined above.
+  optional float distance_m = 7;
+  // Used to verify the list of trusted devices.
+  repeated PublicateCertificate certficate = 8;
+}
+
+message BleFilters {
+  repeated BleFilter filter = 1;
+}
+
+// FilterResult is returned to host when a BLE event matches a Filter.
+message BleFilterResult {
+  optional uint32 id = 1;  // id of the matched Filter.
+  // TODO(b/193756395): replace with BLE event proto.
+  optional bytes raw_data = 2;
+}
+
+message BleFilterResults {
+  repeated BleFilterResult result = 1;
+}
diff --git a/nearby/tests/unit/src/com/android/server/nearby/presence/ChreCommunicationTest.java b/nearby/tests/unit/src/com/android/server/nearby/presence/ChreCommunicationTest.java
new file mode 100644
index 0000000..b221f46
--- /dev/null
+++ b/nearby/tests/unit/src/com/android/server/nearby/presence/ChreCommunicationTest.java
@@ -0,0 +1,128 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * 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 com.android.server.nearby.presence;
+
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import android.hardware.location.ContextHubClient;
+import android.hardware.location.ContextHubInfo;
+import android.hardware.location.ContextHubTransaction;
+import android.hardware.location.NanoAppMessage;
+import android.hardware.location.NanoAppState;
+
+import com.android.server.nearby.injector.ContextHubManagerAdapter;
+import com.android.server.nearby.injector.Injector;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.mockito.ArgumentCaptor;
+import org.mockito.Captor;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+
+import java.util.Collections;
+import java.util.List;
+import java.util.concurrent.Executor;
+
+public class ChreCommunicationTest {
+    @Mock Injector mInjector;
+    @Mock ContextHubManagerAdapter mManager;
+    @Mock ContextHubTransaction<List<NanoAppState>> mTransaction;
+    @Mock ContextHubTransaction.Response<List<NanoAppState>> mTransactionResponse;
+    @Mock ContextHubClient mClient;
+    @Mock ChreCommunication.ContextHubCommsCallback mChreCallback;
+
+    @Captor
+    ArgumentCaptor<ChreCommunication.OnQueryCompleteListener> mOnQueryCompleteListenerCaptor;
+
+    private ChreCommunication mChreCommunication;
+
+    @Before
+    public void setUp() {
+        MockitoAnnotations.initMocks(this);
+        when(mInjector.getContextHubManagerAdapter()).thenReturn(mManager);
+        when(mManager.getContextHubs()).thenReturn(Collections.singletonList(new ContextHubInfo()));
+        when(mManager.queryNanoApps(any())).thenReturn(mTransaction);
+        when(mManager.createClient(any(), any(), any())).thenReturn(mClient);
+        when(mTransactionResponse.getResult()).thenReturn(ContextHubTransaction.RESULT_SUCCESS);
+        when(mTransactionResponse.getContents())
+                .thenReturn(
+                        Collections.singletonList(
+                                new NanoAppState(PresenceManager.NANOAPP_ID, 1, true)));
+
+        mChreCommunication = new ChreCommunication(mInjector, new InlineExecutor());
+        mChreCommunication.start(mChreCallback, Collections.singleton(PresenceManager.NANOAPP_ID));
+
+        verify(mTransaction).setOnCompleteListener(mOnQueryCompleteListenerCaptor.capture(), any());
+        mOnQueryCompleteListenerCaptor.getValue().onComplete(mTransaction, mTransactionResponse);
+    }
+
+    @Test
+    public void testStart() {
+        verify(mChreCallback).started(true);
+    }
+
+    @Test
+    public void testStop() {
+        mChreCommunication.stop();
+        verify(mClient).close();
+    }
+
+    @Test
+    public void testSendMessageToNanApp() {
+        NanoAppMessage message =
+                NanoAppMessage.createMessageToNanoApp(
+                        PresenceManager.NANOAPP_ID,
+                        PresenceManager.NANOAPP_MESSAGE_TYPE_FILTER,
+                        new byte[] {1, 2, 3});
+        mChreCommunication.sendMessageToNanoApp(message);
+        verify(mClient).sendMessageToNanoApp(eq(message));
+    }
+
+    @Test
+    public void testOnMessageFromNanoApp() {
+        NanoAppMessage message =
+                NanoAppMessage.createMessageToNanoApp(
+                        PresenceManager.NANOAPP_ID,
+                        PresenceManager.NANOAPP_MESSAGE_TYPE_FILTER_RESULT,
+                        new byte[] {1, 2, 3});
+        mChreCommunication.onMessageFromNanoApp(mClient, message);
+        verify(mChreCallback).onMessageFromNanoApp(eq(message));
+    }
+
+    @Test
+    public void testOnHubReset() {
+        mChreCommunication.onHubReset(mClient);
+        verify(mChreCallback).onHubReset();
+    }
+
+    @Test
+    public void testOnNanoAppLoaded() {
+        mChreCommunication.onNanoAppLoaded(mClient, PresenceManager.NANOAPP_ID);
+        verify(mChreCallback).onNanoAppRestart(eq(PresenceManager.NANOAPP_ID));
+    }
+
+    private static class InlineExecutor implements Executor {
+        @Override
+        public void execute(Runnable command) {
+            command.run();
+        }
+    }
+}
diff --git a/nearby/tests/unit/src/com/android/server/nearby/presence/PresenceManagerTest.java b/nearby/tests/unit/src/com/android/server/nearby/presence/PresenceManagerTest.java
new file mode 100644
index 0000000..f9676e3
--- /dev/null
+++ b/nearby/tests/unit/src/com/android/server/nearby/presence/PresenceManagerTest.java
@@ -0,0 +1,108 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * 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 com.android.server.nearby.presence;
+
+import static com.android.server.nearby.presence.PresenceManager.NANOAPP_ID;
+import static com.android.server.nearby.presence.PresenceManager.NANOAPP_MESSAGE_TYPE_FILTER_RESULT;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+
+import android.content.Context;
+import android.hardware.location.NanoAppMessage;
+
+import androidx.test.filters.SdkSuppress;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.mockito.ArgumentCaptor;
+import org.mockito.Captor;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+
+import java.util.Collections;
+
+import service.proto.Blefilter;
+
+public class PresenceManagerTest {
+    @Mock private Context mContext;
+    @Mock private PresenceManager.PresenceCallback mPresenceCallback;
+    @Mock private ChreCommunication mChreCommunication;
+
+    @Captor ArgumentCaptor<ChreCommunication.ContextHubCommsCallback> mChreCallbackCaptor;
+    @Captor ArgumentCaptor<NanoAppMessage> mNanoAppMessageCaptor;
+
+    private PresenceManager mPresenceManager;
+
+    @Before
+    public void setup() {
+        MockitoAnnotations.initMocks(this);
+        mPresenceManager = new PresenceManager(mContext, mPresenceCallback);
+    }
+
+    @Test
+    @SdkSuppress(minSdkVersion = 32, codeName = "T")
+    public void testInit() {
+        mPresenceManager.initiate(mChreCommunication);
+        verify(mChreCommunication).start(any(), eq(Collections.singleton(NANOAPP_ID)));
+    }
+
+    @Test
+    @SdkSuppress(minSdkVersion = 32, codeName = "T")
+    public void testOnFilterResults() {
+        Blefilter.BleFilterResults results = Blefilter.BleFilterResults.newBuilder().build();
+        NanoAppMessage chre_message =
+                NanoAppMessage.createMessageToNanoApp(
+                        NANOAPP_ID, NANOAPP_MESSAGE_TYPE_FILTER_RESULT, results.toByteArray());
+        mPresenceManager.initiate(mChreCommunication);
+        verify(mChreCommunication).start(mChreCallbackCaptor.capture(), any());
+        mChreCallbackCaptor.getValue().onMessageFromNanoApp(chre_message);
+        verify(mPresenceCallback).onFilterResults(eq(results));
+    }
+
+    @Test
+    @SdkSuppress(minSdkVersion = 32, codeName = "T")
+    public void testUpdateFiltersBeforeChreStarted() {
+        Blefilter.BleFilters filters = Blefilter.BleFilters.newBuilder().build();
+        mPresenceManager.updateFilters(filters);
+        verify(mChreCommunication, never()).sendMessageToNanoApp(any());
+        mPresenceManager.initiate(mChreCommunication);
+        verify(mChreCommunication).start(mChreCallbackCaptor.capture(), any());
+        mChreCallbackCaptor.getValue().started(true);
+        verify(mChreCommunication, times(1)).sendMessageToNanoApp(mNanoAppMessageCaptor.capture());
+        assertThat(mNanoAppMessageCaptor.getValue().getMessageBody())
+                .isEqualTo(filters.toByteArray());
+    }
+
+    @Test
+    @SdkSuppress(minSdkVersion = 32, codeName = "T")
+    public void testUpdateFiltersAfterChreStarted() {
+        mPresenceManager.initiate(mChreCommunication);
+        verify(mChreCommunication).start(mChreCallbackCaptor.capture(), any());
+        mChreCallbackCaptor.getValue().started(true);
+        Blefilter.BleFilters filters = Blefilter.BleFilters.newBuilder().build();
+        mPresenceManager.updateFilters(filters);
+        verify(mChreCommunication, times(1)).sendMessageToNanoApp(mNanoAppMessageCaptor.capture());
+        assertThat(mNanoAppMessageCaptor.getValue().getMessageBody())
+                .isEqualTo(filters.toByteArray());
+    }
+}
diff --git a/nearby/tests/unit/src/com/android/server/nearby/provider/BleDiscoveryProviderTest.java b/nearby/tests/unit/src/com/android/server/nearby/provider/BleDiscoveryProviderTest.java
index 4c78885..8e97443 100644
--- a/nearby/tests/unit/src/com/android/server/nearby/provider/BleDiscoveryProviderTest.java
+++ b/nearby/tests/unit/src/com/android/server/nearby/provider/BleDiscoveryProviderTest.java
@@ -32,6 +32,7 @@
 
 import androidx.test.platform.app.InstrumentationRegistry;
 
+import com.android.server.nearby.injector.ContextHubManagerAdapter;
 import com.android.server.nearby.injector.Injector;
 
 import org.junit.Before;
@@ -81,6 +82,11 @@
         public BluetoothAdapter getBluetoothAdapter() {
             return mBluetoothAdapter;
         }
+
+        @Override
+        public ContextHubManagerAdapter getContextHubManagerAdapter() {
+            return null;
+        }
     }
 
     private ScanResult createScanResult() {