diff --git a/service/mdns/com/android/server/connectivity/mdns/MdnsAnnouncer.java b/service/mdns/com/android/server/connectivity/mdns/MdnsAnnouncer.java
new file mode 100644
index 0000000..91e08a8
--- /dev/null
+++ b/service/mdns/com/android/server/connectivity/mdns/MdnsAnnouncer.java
@@ -0,0 +1,99 @@
+/*
+ * 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.connectivity.mdns;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.os.Looper;
+
+import com.android.internal.annotations.VisibleForTesting;
+
+import java.net.SocketAddress;
+import java.util.Collections;
+import java.util.List;
+import java.util.function.Supplier;
+
+/**
+ * Sends mDns announcements when a service registration changes and at regular intervals.
+ *
+ * This allows maintaining other hosts' caches up-to-date. See RFC6762 8.3.
+ */
+public class MdnsAnnouncer extends MdnsPacketRepeater<MdnsAnnouncer.AnnouncementInfo> {
+    private static final long ANNOUNCEMENT_INITIAL_DELAY_MS = 1000L;
+    @VisibleForTesting
+    static final int ANNOUNCEMENT_COUNT = 8;
+
+    @NonNull
+    private final String mLogTag;
+
+    static class AnnouncementInfo implements MdnsPacketRepeater.Request {
+        @NonNull
+        private final MdnsPacket mPacket;
+        @NonNull
+        private final Supplier<Iterable<SocketAddress>> mDestinationsSupplier;
+
+        AnnouncementInfo(List<MdnsRecord> announcedRecords, List<MdnsRecord> additionalRecords,
+                Supplier<Iterable<SocketAddress>> destinationsSupplier) {
+            // Records to announce (as answers)
+            // Records to place in the "Additional records", with NSEC negative responses
+            // to mark records that have been verified unique
+            final int flags = 0x8400; // Response, authoritative (rfc6762 18.4)
+            mPacket = new MdnsPacket(flags,
+                    Collections.emptyList() /* questions */,
+                    announcedRecords,
+                    Collections.emptyList() /* authorityRecords */,
+                    additionalRecords);
+            mDestinationsSupplier = destinationsSupplier;
+        }
+
+        @Override
+        public MdnsPacket getPacket(int index) {
+            return mPacket;
+        }
+
+        @Override
+        public Iterable<SocketAddress> getDestinations(int index) {
+            return mDestinationsSupplier.get();
+        }
+
+        @Override
+        public long getDelayMs(int nextIndex) {
+            // Delay is doubled for each announcement
+            return ANNOUNCEMENT_INITIAL_DELAY_MS << (nextIndex - 1);
+        }
+
+        @Override
+        public int getNumSends() {
+            return ANNOUNCEMENT_COUNT;
+        }
+    }
+
+    public MdnsAnnouncer(@NonNull String interfaceTag, @NonNull Looper looper,
+            @NonNull MdnsReplySender replySender,
+            @Nullable PacketRepeaterCallback<AnnouncementInfo> cb) {
+        super(looper, replySender, cb);
+        mLogTag = MdnsAnnouncer.class.getSimpleName() + "/" + interfaceTag;
+    }
+
+    @Override
+    protected String getTag() {
+        return mLogTag;
+    }
+
+    // TODO: Notify MdnsRecordRepository that the records were announced for that service ID,
+    // so it can update the last advertised timestamp of the associated records.
+}
diff --git a/tests/unit/java/com/android/server/connectivity/mdns/MdnsAnnouncerTest.kt b/tests/unit/java/com/android/server/connectivity/mdns/MdnsAnnouncerTest.kt
new file mode 100644
index 0000000..e9325d5
--- /dev/null
+++ b/tests/unit/java/com/android/server/connectivity/mdns/MdnsAnnouncerTest.kt
@@ -0,0 +1,283 @@
+/*
+ * 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.connectivity.mdns
+
+import android.net.InetAddresses.parseNumericAddress
+import android.os.Build
+import android.os.HandlerThread
+import android.os.SystemClock
+import com.android.internal.util.HexDump
+import com.android.server.connectivity.mdns.MdnsAnnouncer.AnnouncementInfo
+import com.android.testutils.DevSdkIgnoreRule.IgnoreUpTo
+import com.android.testutils.DevSdkIgnoreRunner
+import java.net.DatagramPacket
+import java.net.Inet6Address
+import java.net.InetAddress
+import java.net.InetSocketAddress
+import java.net.MulticastSocket
+import kotlin.test.assertEquals
+import kotlin.test.assertTrue
+import org.junit.After
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.mockito.ArgumentCaptor
+import org.mockito.Mockito.any
+import org.mockito.Mockito.atLeast
+import org.mockito.Mockito.mock
+import org.mockito.Mockito.timeout
+import org.mockito.Mockito.verify
+
+private const val FIRST_ANNOUNCES_DELAY = 100L
+private const val FIRST_ANNOUNCES_COUNT = 2
+private const val NEXT_ANNOUNCES_DELAY = 1L
+private const val TEST_TIMEOUT_MS = 1000L
+
+private val destinationsSupplier = {
+    listOf(InetSocketAddress(MdnsConstants.getMdnsIPv6Address(), MdnsConstants.MDNS_PORT)) }
+
+@RunWith(DevSdkIgnoreRunner::class)
+@IgnoreUpTo(Build.VERSION_CODES.S_V2)
+class MdnsAnnouncerTest {
+
+    private val thread = HandlerThread(MdnsAnnouncerTest::class.simpleName)
+    private val socket = mock(MulticastSocket::class.java)
+    private val buffer = ByteArray(1500)
+
+    @Before
+    fun setUp() {
+        thread.start()
+    }
+
+    @After
+    fun tearDown() {
+        thread.quitSafely()
+    }
+
+    private class TestAnnouncementInfo(
+        announcedRecords: List<MdnsRecord>,
+        additionalRecords: List<MdnsRecord>
+    )
+        : AnnouncementInfo(announcedRecords, additionalRecords, destinationsSupplier) {
+        override fun getDelayMs(nextIndex: Int) =
+                if (nextIndex < FIRST_ANNOUNCES_COUNT) {
+                    FIRST_ANNOUNCES_DELAY
+                } else {
+                    NEXT_ANNOUNCES_DELAY
+                }
+    }
+
+    @Test
+    fun testAnnounce() {
+        val replySender = MdnsReplySender(thread.looper, socket, buffer)
+        @Suppress("UNCHECKED_CAST")
+        val cb = mock(MdnsPacketRepeater.PacketRepeaterCallback::class.java)
+                as MdnsPacketRepeater.PacketRepeaterCallback<AnnouncementInfo>
+        val announcer = MdnsAnnouncer("testiface", thread.looper, replySender, cb)
+        /*
+        The expected packet replicates records announced when registering a service, as observed in
+        the legacy mDNS implementation (some ordering differs to be more readable).
+        Obtained with scapy 2.5.0 RC3 (2.4.5 does not compress TLDs like .arpa properly) with:
+        scapy.raw(scapy.dns_compress(scapy.DNS(rd=0, qr=1, aa=1,
+        qd = None,
+        an =
+        scapy.DNSRR(type='PTR', rrname='123.0.2.192.in-addr.arpa.', rdata='Android.local',
+            rclass=0x8001, ttl=120) /
+        scapy.DNSRR(type='PTR',
+            rrname='3.2.1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.B.D.0.1.0.0.2.ip6.arpa',
+            rdata='Android.local', rclass=0x8001, ttl=120) /
+        scapy.DNSRR(type='PTR',
+            rrname='6.5.4.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.B.D.0.1.0.0.2.ip6.arpa',
+            rdata='Android.local', rclass=0x8001, ttl=120) /
+        scapy.DNSRR(type='PTR', rrname='_testtype._tcp.local',
+            rdata='testservice._testtype._tcp.local', rclass='IN', ttl=4500) /
+	    scapy.DNSRRSRV(rrname='testservice._testtype._tcp.local', rclass=0x8001, port=31234,
+	        target='Android.local', ttl=120) /
+	    scapy.DNSRR(type='TXT', rrname='testservice._testtype._tcp.local', rclass=0x8001, rdata='',
+	        ttl=4500) /
+        scapy.DNSRR(type='A', rrname='Android.local', rclass=0x8001, rdata='192.0.2.123', ttl=120) /
+        scapy.DNSRR(type='AAAA', rrname='Android.local', rclass=0x8001, rdata='2001:db8::123',
+            ttl=120) /
+        scapy.DNSRR(type='AAAA', rrname='Android.local', rclass=0x8001, rdata='2001:db8::456',
+            ttl=120),
+        ar =
+        scapy.DNSRRNSEC(rrname='123.0.2.192.in-addr.arpa.', rclass=0x8001, ttl=120,
+            nextname='123.0.2.192.in-addr.arpa.', typebitmaps=[12]) /
+        scapy.DNSRRNSEC(
+            rrname='3.2.1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.B.D.0.1.0.0.2.ip6.arpa',
+            rclass=0x8001, ttl=120,
+            nextname='3.2.1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.B.D.0.1.0.0.2.ip6.arpa',
+            typebitmaps=[12]) /
+        scapy.DNSRRNSEC(
+            rrname='6.5.4.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.B.D.0.1.0.0.2.ip6.arpa',
+            rclass=0x8001, ttl=120,
+            nextname='6.5.4.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.B.D.0.1.0.0.2.ip6.arpa',
+            typebitmaps=[12]) /
+	    scapy.DNSRRNSEC(
+	        rrname='testservice._testtype._tcp.local', rclass=0x8001, ttl=4500,
+	        nextname='testservice._testtype._tcp.local', typebitmaps=[16, 33]) /
+        scapy.DNSRRNSEC(
+            rrname='Android.local', rclass=0x8001, ttl=120, nextname='Android.local',
+            typebitmaps=[1, 28]))
+        )).hex().upper()
+        */
+        val expected = "00008400000000090000000503313233013001320331393207696E2D61646472046172706" +
+                "100000C800100000078000F07416E64726F6964056C6F63616C00013301320131013001300130013" +
+                "00130013001300130013001300130013001300130013001300130013001300130013001380142014" +
+                "40130013101300130013203697036C020000C8001000000780002C030013601350134C045000C800" +
+                "1000000780002C030095F7465737474797065045F746370C038000C000100001194000E0B7465737" +
+                "473657276696365C0A5C0C000218001000000780008000000007A02C030C0C000108001000011940" +
+                "000C03000018001000000780004C000027BC030001C800100000078001020010DB80000000000000" +
+                "00000000123C030001C800100000078001020010DB8000000000000000000000456C00C002F80010" +
+                "00000780006C00C00020008C03F002F8001000000780006C03F00020008C091002F8001000000780" +
+                "006C09100020008C0C0002F8001000011940009C0C000050000800040C030002F800100000078000" +
+                "8C030000440000008"
+
+        val hostname = arrayOf("Android", "local")
+        val serviceType = arrayOf("_testtype", "_tcp", "local")
+        val serviceName = arrayOf("testservice", "_testtype", "_tcp", "local")
+        val v4Addr = parseNumericAddress("192.0.2.123")
+        val v6Addr1 = parseNumericAddress("2001:DB8::123")
+        val v6Addr2 = parseNumericAddress("2001:DB8::456")
+        val v4AddrRev = arrayOf("123", "0", "2", "192", "in-addr", "arpa")
+        val v6Addr1Rev = getReverseV6AddressName(v6Addr1)
+        val v6Addr2Rev = getReverseV6AddressName(v6Addr2)
+
+        val announcedRecords = listOf(
+                // Reverse address records
+                MdnsPointerRecord(v4AddrRev,
+                        0L /* receiptTimeMillis */,
+                        true /* cacheFlush */,
+                        120000L /* ttlMillis */,
+                        hostname),
+                MdnsPointerRecord(v6Addr1Rev,
+                        0L /* receiptTimeMillis */,
+                        true /* cacheFlush */,
+                        120000L /* ttlMillis */,
+                        hostname),
+                MdnsPointerRecord(v6Addr2Rev,
+                        0L /* receiptTimeMillis */,
+                        true /* cacheFlush */,
+                        120000L /* ttlMillis */,
+                        hostname),
+                // Service registration records (RFC6763)
+                MdnsPointerRecord(
+                        serviceType,
+                        0L /* receiptTimeMillis */,
+                        // Not a unique name owned by the announcer, so cacheFlush=false
+                        false /* cacheFlush */,
+                        4500000L /* ttlMillis */,
+                        serviceName),
+                MdnsServiceRecord(
+                        serviceName,
+                        0L /* receiptTimeMillis */,
+                        true /* cacheFlush */,
+                        120000L /* ttlMillis */,
+                        0 /* servicePriority */,
+                        0 /* serviceWeight */,
+                        31234 /* servicePort */,
+                        hostname),
+                MdnsTextRecord(
+                        serviceName,
+                        0L /* receiptTimeMillis */,
+                        true /* cacheFlush */,
+                        4500000L /* ttlMillis */,
+                        emptyList() /* entries */),
+                // Address records for the hostname
+                MdnsInetAddressRecord(hostname,
+                        0L /* receiptTimeMillis */,
+                        true /* cacheFlush */,
+                        120000L /* ttlMillis */,
+                        v4Addr),
+                MdnsInetAddressRecord(hostname,
+                        0L /* receiptTimeMillis */,
+                        true /* cacheFlush */,
+                        120000L /* ttlMillis */,
+                        v6Addr1),
+                MdnsInetAddressRecord(hostname,
+                        0L /* receiptTimeMillis */,
+                        true /* cacheFlush */,
+                        120000L /* ttlMillis */,
+                        v6Addr2))
+        // Negative responses (RFC6762 6.1)
+        val additionalRecords = listOf(
+                MdnsNsecRecord(v4AddrRev,
+                        0L /* receiptTimeMillis */,
+                        true /* cacheFlush */,
+                        120000L /* ttlMillis */,
+                        v4AddrRev,
+                        intArrayOf(MdnsRecord.TYPE_PTR)),
+                MdnsNsecRecord(v6Addr1Rev,
+                        0L /* receiptTimeMillis */,
+                        true /* cacheFlush */,
+                        120000L /* ttlMillis */,
+                        v6Addr1Rev,
+                        intArrayOf(MdnsRecord.TYPE_PTR)),
+                MdnsNsecRecord(v6Addr2Rev,
+                        0L /* receiptTimeMillis */,
+                        true /* cacheFlush */,
+                        120000L /* ttlMillis */,
+                        v6Addr2Rev,
+                        intArrayOf(MdnsRecord.TYPE_PTR)),
+                MdnsNsecRecord(serviceName,
+                        0L /* receiptTimeMillis */,
+                        true /* cacheFlush */,
+                        4500000L /* ttlMillis */,
+                        serviceName,
+                        intArrayOf(MdnsRecord.TYPE_TXT, MdnsRecord.TYPE_SRV)),
+                MdnsNsecRecord(hostname,
+                        0L /* receiptTimeMillis */,
+                        true /* cacheFlush */,
+                        120000L /* ttlMillis */,
+                        hostname,
+                        intArrayOf(MdnsRecord.TYPE_A, MdnsRecord.TYPE_AAAA)))
+        val request = TestAnnouncementInfo(announcedRecords, additionalRecords)
+
+        val timeStart = SystemClock.elapsedRealtime()
+        val startDelay = 50L
+        val sendId = 1
+        announcer.startSending(sendId, request, startDelay)
+
+        val captor = ArgumentCaptor.forClass(DatagramPacket::class.java)
+        repeat(FIRST_ANNOUNCES_COUNT) { i ->
+            verify(cb, timeout(TEST_TIMEOUT_MS)).onSent(i, request)
+            verify(socket, atLeast(i + 1)).send(any())
+            val now = SystemClock.elapsedRealtime()
+            assertTrue(now > timeStart + startDelay + i * FIRST_ANNOUNCES_DELAY)
+            assertTrue(now < timeStart + startDelay + (i + 1) * FIRST_ANNOUNCES_DELAY)
+        }
+
+        // Subsequent announces should happen quickly (NEXT_ANNOUNCES_DELAY)
+        verify(socket, timeout(TEST_TIMEOUT_MS).times(MdnsAnnouncer.ANNOUNCEMENT_COUNT))
+                .send(captor.capture())
+        verify(cb, timeout(TEST_TIMEOUT_MS)).onFinished(request)
+
+        captor.allValues.forEach {
+            assertEquals(expected, HexDump.toHexString(it.data))
+        }
+    }
+}
+
+/**
+ * Compute 2001:db8::1 --> 1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.B.D.1.0.0.2.ip6.arpa
+ */
+private fun getReverseV6AddressName(addr: InetAddress): Array<String> {
+    assertTrue(addr is Inet6Address)
+    return addr.address.flatMapTo(mutableListOf("arpa", "ip6")) {
+        HexDump.toHexString(it).toCharArray().map(Char::toString)
+    }.reversed().toTypedArray()
+}