diff --git a/application/src/main/resources/thingsboard.yml b/application/src/main/resources/thingsboard.yml
index 889df54848..d5b8cfe15e 100644
--- a/application/src/main/resources/thingsboard.yml
+++ b/application/src/main/resources/thingsboard.yml
@@ -1157,7 +1157,7 @@ transport:
       # - A value of 0 means we accept using CID but will not generate one for foreign peer (enables support but not for incoming traffic).
       # - A value between 0 and <= 4: SingleNodeConnectionIdGenerator is used
       # - A value that are > 4: MultiNodeConnectionIdGenerator is used
-      connection_id_length: "${LWM2M_DTLS_CONNECTION_ID_LENGTH:}"
+      connection_id_length: "${LWM2M_DTLS_CONNECTION_ID_LENGTH:8}"
     server:
       # LwM2M Server ID
       id: "${LWM2M_SERVER_ID:123}"
@@ -1345,7 +1345,7 @@ coap:
     # - A value of 0 means we accept using CID but will not generate one for foreign peer (enables support but not for incoming traffic).
     # - A value between 0 and <= 4: SingleNodeConnectionIdGenerator is used
     # - A value that are > 4: MultiNodeConnectionIdGenerator is used
-    connection_id_length: "${COAP_DTLS_CONNECTION_ID_LENGTH:}"
+    connection_id_length: "${COAP_DTLS_CONNECTION_ID_LENGTH:8}"
     # Specify the MTU (Maximum Transmission Unit).
     # Should be used if LAN MTU is not used, e.g. if IP tunnels are used or if the client uses a smaller value than the LAN MTU.
     # Default = 1024
diff --git a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLength0Test.java b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLength0Test.java
index 7a0b0f8580..a3229a7c19 100644
--- a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLength0Test.java
+++ b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLength0Test.java
@@ -29,10 +29,12 @@ import org.thingsboard.server.dao.service.DaoSqlTest;
 public abstract class AbstractSecurityLwM2MIntegrationDtlsCidLength0Test extends AbstractSecurityLwM2MIntegrationDtlsCidLengthTest {
 
 
+    private static final Integer serverDtlsCidLength = 0;
+
     protected void  testNoSecDtlsCidLength(Integer dtlsCidLength) throws Exception {
-        testNoSecDtlsCidLength(dtlsCidLength, 0);
+        testNoSecDtlsCidLength(dtlsCidLength, serverDtlsCidLength);
     }
     protected void  testPskDtlsCidLength(Integer dtlsCidLength) throws Exception {
-        testPskDtlsCidLength(dtlsCidLength, 0);
+        testPskDtlsCidLength(dtlsCidLength, serverDtlsCidLength);
     }
 }
diff --git a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLength16Test.java b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLength16Test.java
new file mode 100644
index 0000000000..1f5d2d9f19
--- /dev/null
+++ b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLength16Test.java
@@ -0,0 +1,40 @@
+/**
+ * Copyright © 2016-2025 The Thingsboard Authors
+ *
+ * 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.thingsboard.server.transport.lwm2m.security.cid;
+
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.test.context.TestPropertySource;
+import org.thingsboard.server.dao.service.DaoSqlTest;
+
+
+@TestPropertySource(properties = {
+        "transport.lwm2m.dtls.connection_id_length=16"
+})
+
+@DaoSqlTest
+@Slf4j
+public abstract class AbstractSecurityLwM2MIntegrationDtlsCidLength16Test extends AbstractSecurityLwM2MIntegrationDtlsCidLengthTest {
+
+    private static final Integer  serverDtlsCidLength = 16;
+
+    protected void  testNoSecDtlsCidLength(Integer clientDtlsCidLength) throws Exception {
+        testNoSecDtlsCidLength(clientDtlsCidLength, serverDtlsCidLength);
+    }
+
+    protected void  testPskDtlsCidLength(Integer clientDtlsCidLength) throws Exception {
+        testPskDtlsCidLength(clientDtlsCidLength, serverDtlsCidLength);
+    }
+}
diff --git a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLength3Test.java b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLength1Test.java
similarity index 78%
rename from application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLength3Test.java
rename to application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLength1Test.java
index 8a65e28975..a36a618bcf 100644
--- a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLength3Test.java
+++ b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLength1Test.java
@@ -21,17 +21,20 @@ import org.thingsboard.server.dao.service.DaoSqlTest;
 
 
 @TestPropertySource(properties = {
-        "transport.lwm2m.dtls.connection_id_length=3"
+        "transport.lwm2m.dtls.connection_id_length=1"
 })
 
 @DaoSqlTest
 @Slf4j
-public abstract class AbstractSecurityLwM2MIntegrationDtlsCidLength3Test extends AbstractSecurityLwM2MIntegrationDtlsCidLengthTest {
+public abstract class AbstractSecurityLwM2MIntegrationDtlsCidLength1Test extends AbstractSecurityLwM2MIntegrationDtlsCidLengthTest {
+
+
+    private static final Integer serverDtlsCidLength = 1;
 
     protected void  testNoSecDtlsCidLength(Integer dtlsCidLength) throws Exception {
-        testNoSecDtlsCidLength(dtlsCidLength, 3);
+        testNoSecDtlsCidLength(dtlsCidLength, serverDtlsCidLength);
     }
     protected void  testPskDtlsCidLength(Integer dtlsCidLength) throws Exception {
-        testPskDtlsCidLength(dtlsCidLength, 3);
+        testPskDtlsCidLength(dtlsCidLength, serverDtlsCidLength);
     }
 }
diff --git a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLength2Test.java b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLength2Test.java
new file mode 100644
index 0000000000..1cb657e4a4
--- /dev/null
+++ b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLength2Test.java
@@ -0,0 +1,39 @@
+/**
+ * Copyright © 2016-2025 The Thingsboard Authors
+ *
+ * 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.thingsboard.server.transport.lwm2m.security.cid;
+
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.test.context.TestPropertySource;
+import org.thingsboard.server.dao.service.DaoSqlTest;
+
+
+@TestPropertySource(properties = {
+        "transport.lwm2m.dtls.connection_id_length=2"
+})
+
+@DaoSqlTest
+@Slf4j
+public abstract class AbstractSecurityLwM2MIntegrationDtlsCidLength2Test extends AbstractSecurityLwM2MIntegrationDtlsCidLengthTest {
+
+    private static final Integer  serverDtlsCidLength = 2;
+
+    protected void  testNoSecDtlsCidLength(Integer dtlsCidLength) throws Exception {
+        testNoSecDtlsCidLength(dtlsCidLength, serverDtlsCidLength);
+    }
+    protected void  testPskDtlsCidLength(Integer dtlsCidLength) throws Exception {
+        testPskDtlsCidLength(dtlsCidLength, serverDtlsCidLength);
+    }
+}
diff --git a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLength4Test.java b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLength4Test.java
new file mode 100644
index 0000000000..56e544243f
--- /dev/null
+++ b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLength4Test.java
@@ -0,0 +1,39 @@
+/**
+ * Copyright © 2016-2025 The Thingsboard Authors
+ *
+ * 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.thingsboard.server.transport.lwm2m.security.cid;
+
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.test.context.TestPropertySource;
+import org.thingsboard.server.dao.service.DaoSqlTest;
+
+
+@TestPropertySource(properties = {
+        "transport.lwm2m.dtls.connection_id_length=4"
+})
+
+@DaoSqlTest
+@Slf4j
+public abstract class AbstractSecurityLwM2MIntegrationDtlsCidLength4Test extends AbstractSecurityLwM2MIntegrationDtlsCidLengthTest {
+
+    private static final Integer  serverDtlsCidLength = 4;
+
+    protected void  testNoSecDtlsCidLength(Integer dtlsCidLength) throws Exception {
+        testNoSecDtlsCidLength(dtlsCidLength, serverDtlsCidLength);
+    }
+    protected void  testPskDtlsCidLength(Integer dtlsCidLength) throws Exception {
+        testPskDtlsCidLength(dtlsCidLength, serverDtlsCidLength);
+    }
+}
diff --git a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLengthNullTest.java b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLengthNullTest.java
index 9d52920072..6dea2f54d0 100644
--- a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLengthNullTest.java
+++ b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLengthNullTest.java
@@ -28,11 +28,12 @@ import org.thingsboard.server.dao.service.DaoSqlTest;
 @Slf4j
 public abstract class AbstractSecurityLwM2MIntegrationDtlsCidLengthNullTest extends AbstractSecurityLwM2MIntegrationDtlsCidLengthTest {
 
+    private static final Integer  serverDtlsCidLength = null;
 
     protected void  testNoSecDtlsCidLength(Integer dtlsCidLength) throws Exception {
-        testNoSecDtlsCidLength(dtlsCidLength, null);
+        testNoSecDtlsCidLength(dtlsCidLength, serverDtlsCidLength);
     }
     protected void  testPskDtlsCidLength(Integer dtlsCidLength) throws Exception {
-        testPskDtlsCidLength(dtlsCidLength, null);
+        testPskDtlsCidLength(dtlsCidLength, serverDtlsCidLength);
     }
 }
diff --git a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLengthTest.java b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLengthTest.java
index eb17f2cf7e..04afef0c61 100644
--- a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLengthTest.java
+++ b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/AbstractSecurityLwM2MIntegrationDtlsCidLengthTest.java
@@ -17,14 +17,23 @@ package org.thingsboard.server.transport.lwm2m.security.cid;
 
 import lombok.extern.slf4j.Slf4j;
 import org.eclipse.californium.elements.config.Configuration;
+import org.eclipse.californium.scandium.DTLSConnector;
+import org.eclipse.californium.scandium.dtls.Connection;
+import org.eclipse.californium.scandium.dtls.ConnectionId;
+import org.eclipse.californium.scandium.dtls.InMemoryReadWriteLockConnectionStore;
+import org.eclipse.californium.scandium.dtls.ResumptionSupportingConnectionStore;
 import org.eclipse.leshan.client.californium.endpoint.CaliforniumClientEndpoint;
 import org.eclipse.leshan.client.californium.endpoint.CaliforniumClientEndpointsProvider;
+import org.eclipse.leshan.client.servers.LwM2mServer;
+import org.eclipse.leshan.core.peer.IpPeer;
 import org.junit.Assert;
 import org.thingsboard.server.common.data.Device;
 import org.thingsboard.server.common.data.DeviceProfile;
 import org.thingsboard.server.dao.service.DaoSqlTest;
 import org.thingsboard.server.transport.lwm2m.security.AbstractSecurityLwM2MIntegrationTest;
 
+import java.lang.reflect.Field;
+import java.net.InetSocketAddress;
 import java.util.concurrent.TimeUnit;
 
 import static org.awaitility.Awaitility.await;
@@ -39,13 +48,13 @@ public abstract class AbstractSecurityLwM2MIntegrationDtlsCidLengthTest extends
 
     protected String awaitAlias;
 
-    protected void testNoSecDtlsCidLength(Integer dtlsCidLength, Integer serverDtlsCidLength) throws Exception {
+    protected void testNoSecDtlsCidLength(Integer clientDtlsCidLength, Integer serverDtlsCidLength) throws Exception {
         initDeviceCredentialsNoSek();
-        basicTestConnectionDtlsCidLength(dtlsCidLength, serverDtlsCidLength);
+        basicTestConnectionDtlsCidLength(clientDtlsCidLength, serverDtlsCidLength);
     }
-    protected void testPskDtlsCidLength(Integer dtlsCidLength, Integer serverDtlsCidLength) throws Exception {
+    protected void testPskDtlsCidLength(Integer clientDtlsCidLength, Integer serverDtlsCidLength) throws Exception {
         initDeviceCredentialsPsk();
-        basicTestConnectionDtlsCidLength(dtlsCidLength, serverDtlsCidLength);
+        basicTestConnectionDtlsCidLength(clientDtlsCidLength, serverDtlsCidLength);
     }
 
     protected void basicTestConnectionDtlsCidLength(Integer clientDtlsCidLength,
@@ -69,19 +78,55 @@ public abstract class AbstractSecurityLwM2MIntegrationDtlsCidLengthTest extends
             Assert.assertTrue(lwM2MTestClient.getClientDtlsCid().isEmpty());
         } else {
             Assert.assertEquals(2L, lwM2MTestClient.getClientDtlsCid().size());
-            Assert.assertTrue(lwM2MTestClient.getClientDtlsCid().keySet().contains(ON_READ_CONNECTION_ID));
-            Assert.assertTrue(lwM2MTestClient.getClientDtlsCid().keySet().contains(ON_WRITE_CONNECTION_ID));
-            if (serverDtlsCidLength == null) {
+            Assert.assertTrue(lwM2MTestClient.getClientDtlsCid().containsKey(ON_READ_CONNECTION_ID));
+            Assert.assertTrue(lwM2MTestClient.getClientDtlsCid().containsKey(ON_WRITE_CONNECTION_ID));
+
+            LwM2mServer lwM2mServer = lwM2MTestClient.getLeshanClient().getRegisteredServers().entrySet().stream().findFirst().get().getValue();
+            CaliforniumClientEndpoint  lwM2mClientEndpoint  = (CaliforniumClientEndpoint) lwM2MTestClient.getLeshanClient().getEndpoint(lwM2mServer);
+            Connection connection = getConnection(lwM2mClientEndpoint, lwM2mServer);
+            ConnectionId clientCid = connection.getConnectionId();
+            ConnectionId readCid = connection.getEstablishedDtlsContext().getReadConnectionId();
+            ConnectionId serverCid = connection.getEstablishedDtlsContext().getWriteConnectionId();
+            if (serverDtlsCidLength == null || clientDtlsCidLength == null) {
+                // cid is not used
                 Assert.assertNull(lwM2MTestClient.getClientDtlsCid().get(ON_WRITE_CONNECTION_ID));
                 Assert.assertNull(lwM2MTestClient.getClientDtlsCid().get(ON_READ_CONNECTION_ID));
+                Assert.assertNull(readCid);
+                Assert.assertNull(serverCid);
             } else {
+                Assert.assertEquals(serverDtlsCidLength, lwM2MTestClient.getClientDtlsCid().get(ON_WRITE_CONNECTION_ID));
                 Assert.assertEquals(clientDtlsCidLength, lwM2MTestClient.getClientDtlsCid().get(ON_READ_CONNECTION_ID));
-                if (clientDtlsCidLength == null) {
-                    Assert.assertNull(lwM2MTestClient.getClientDtlsCid().get(ON_READ_CONNECTION_ID));
+                // cid used
+                Assert.assertNotNull(clientCid);
+                Assert.assertNotNull(readCid);
+                if (clientDtlsCidLength > 0) {
+                    Assert.assertEquals(clientCid, readCid);
+                }
+                Assert.assertNotNull(serverCid);
+                int actualServerCidLength = serverCid.getBytes().length;
+                int expectedServerCidLength = serverDtlsCidLength;
+                Assert.assertEquals(expectedServerCidLength, actualServerCidLength);
+            }
+
+            if (clientCid != null) {
+                int actualClientCidLength = clientCid.getBytes().length;
+                int expectedClientCidLength;
+                if (clientDtlsCidLength == null || clientDtlsCidLength == 0) {
+                    expectedClientCidLength = 3;
                 } else {
-                    Assert.assertEquals(Integer.valueOf(serverDtlsCidLength), lwM2MTestClient.getClientDtlsCid().get(ON_WRITE_CONNECTION_ID));
+                    expectedClientCidLength = clientDtlsCidLength;
                 }
+                Assert.assertEquals(expectedClientCidLength, actualClientCidLength);
             }
         }
     }
+
+    private static Connection getConnection(CaliforniumClientEndpoint lwM2mClientEndpoint, LwM2mServer lwM2mServer) throws NoSuchFieldException, IllegalAccessException {
+        DTLSConnector connector = (DTLSConnector) lwM2mClientEndpoint.getCoapEndpoint().getConnector();
+        Field field = DTLSConnector.class.getDeclaredField("connectionStore");
+        field.setAccessible(true);
+        ResumptionSupportingConnectionStore connectionStore = (InMemoryReadWriteLockConnectionStore) field.get(connector);
+        InetSocketAddress serverAddr = ((IpPeer) lwM2mServer.getTransportData()).getSocketAddress();
+        return connectionStore.get(serverAddr);
+    }
 }
diff --git a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_0/NoSecLwM2MIntegrationDtlsCidLengthTest.java b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_0/NoSecLwM2MIntegrationDtlsCidLengthTest.java
index 6d529b3c08..2b5cccd7be 100644
--- a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_0/NoSecLwM2MIntegrationDtlsCidLengthTest.java
+++ b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_0/NoSecLwM2MIntegrationDtlsCidLengthTest.java
@@ -27,7 +27,7 @@ public class NoSecLwM2MIntegrationDtlsCidLengthTest extends AbstractSecurityLwM2
     @Before
     public void setUpNoSecDtlsCidLength() {
         transportConfiguration = getTransportConfiguration(OBSERVE_ATTRIBUTES_WITHOUT_PARAMS, getBootstrapServerCredentialsSecure(NO_SEC, NONE));
-        awaitAlias = "await on client state (NoSec_Lwm2m) DtlsCidLength = 0";
+        awaitAlias = "await on client state (NoSec_Lwm2m) serverDtlsCidLength = 0";
     }
 
     @Test
@@ -40,8 +40,23 @@ public class NoSecLwM2MIntegrationDtlsCidLengthTest extends AbstractSecurityLwM2
         testNoSecDtlsCidLength(0);
     }
 
+    @Test
+    public void testWithNoSecConnectLwm2mSuccessClientDtlsCidLength_1() throws Exception {
+        testNoSecDtlsCidLength(1);
+    }
+
     @Test
     public void testWithNoSecConnectLwm2mSuccessClientDtlsCidLength_2() throws Exception {
-        testNoSecDtlsCidLength(2);
+        testNoSecDtlsCidLength(1);
+    }
+
+    @Test
+    public void testWithNoSecConnectLwm2mSuccessClientDtlsCidLength_4() throws Exception {
+        testNoSecDtlsCidLength(4);
+    }
+
+    @Test
+    public void testWithNoSecConnectLwm2mSuccessClientDtlsCidLength_16() throws Exception {
+        testNoSecDtlsCidLength(16);
     }
 }
diff --git a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_0/PskLwm2mIntegrationDtlsCidLengthTest.java b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_0/PskLwm2mIntegrationDtlsCidLengthTest.java
index f478a18777..c08eeeaa79 100644
--- a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_0/PskLwm2mIntegrationDtlsCidLengthTest.java
+++ b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_0/PskLwm2mIntegrationDtlsCidLengthTest.java
@@ -27,7 +27,7 @@ public class PskLwm2mIntegrationDtlsCidLengthTest extends AbstractSecurityLwM2MI
     @Before
     public void createProfileRpc() {
         transportConfiguration = getTransportConfiguration(OBSERVE_ATTRIBUTES_WITHOUT_PARAMS, getBootstrapServerCredentialsSecure(PSK, NONE));
-        awaitAlias = "await on client state (Psk_Lwm2m) DtlsCidLength = 0";
+        awaitAlias = "await on client state (Psk_Lwm2m) serverDtlsCidLength = 0";
     }
 
     @Test
@@ -39,10 +39,24 @@ public class PskLwm2mIntegrationDtlsCidLengthTest extends AbstractSecurityLwM2MI
     public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_0() throws Exception {
         testPskDtlsCidLength(0);
     }
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_1() throws Exception {
+        testPskDtlsCidLength(1);
+    }
 
     @Test
     public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_2() throws Exception {
         testPskDtlsCidLength(2);
     }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_4() throws Exception {
+        testPskDtlsCidLength(4);
+    }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_16() throws Exception {
+        testPskDtlsCidLength(16);
+    }
 }
 
diff --git a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_1/PskLwm2mIntegrationDtlsCidLengthTest.java b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_1/PskLwm2mIntegrationDtlsCidLengthTest.java
new file mode 100644
index 0000000000..b2c06495fc
--- /dev/null
+++ b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_1/PskLwm2mIntegrationDtlsCidLengthTest.java
@@ -0,0 +1,64 @@
+/**
+ * Copyright © 2016-2025 The Thingsboard Authors
+ *
+ * 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.thingsboard.server.transport.lwm2m.security.cid.serverDtlsCidLength_1;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.thingsboard.server.transport.lwm2m.security.cid.AbstractSecurityLwM2MIntegrationDtlsCidLength0Test;
+import org.thingsboard.server.transport.lwm2m.security.cid.AbstractSecurityLwM2MIntegrationDtlsCidLength1Test;
+
+import static org.thingsboard.server.common.data.device.credentials.lwm2m.LwM2MSecurityMode.PSK;
+import static org.thingsboard.server.transport.lwm2m.Lwm2mTestHelper.LwM2MProfileBootstrapConfigType.NONE;
+
+public class PskLwm2mIntegrationDtlsCidLengthTest extends AbstractSecurityLwM2MIntegrationDtlsCidLength1Test {
+
+    @Before
+    public void createProfileRpc() {
+        transportConfiguration = getTransportConfiguration(OBSERVE_ATTRIBUTES_WITHOUT_PARAMS, getBootstrapServerCredentialsSecure(PSK, NONE));
+        awaitAlias = "await on client state (Psk_Lwm2m) serverDtlsCidLength = 1";
+    }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_Null() throws Exception {
+        testPskDtlsCidLength(null);
+    }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_0() throws Exception {
+        testPskDtlsCidLength(0);
+    }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_1() throws Exception {
+        testPskDtlsCidLength(1);
+    }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_2() throws Exception {
+        testPskDtlsCidLength(2);
+    }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_4() throws Exception {
+        testPskDtlsCidLength(4);
+    }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_16() throws Exception {
+        testPskDtlsCidLength(16);
+    }
+}
+
diff --git a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_3/NoSecLwM2MIntegrationDtlsCidLengthTest.java b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_16/NoSecLwM2MIntegrationDtlsCidLengthTest.java
similarity index 69%
rename from application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_3/NoSecLwM2MIntegrationDtlsCidLengthTest.java
rename to application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_16/NoSecLwM2MIntegrationDtlsCidLengthTest.java
index a395f2e7e3..872608145c 100644
--- a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_3/NoSecLwM2MIntegrationDtlsCidLengthTest.java
+++ b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_16/NoSecLwM2MIntegrationDtlsCidLengthTest.java
@@ -13,21 +13,22 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package org.thingsboard.server.transport.lwm2m.security.cid.serverDtlsCidLength_3;
+package org.thingsboard.server.transport.lwm2m.security.cid.serverDtlsCidLength_16;
 
 import org.junit.Before;
 import org.junit.Test;
-import org.thingsboard.server.transport.lwm2m.security.cid.AbstractSecurityLwM2MIntegrationDtlsCidLength3Test;
+import org.thingsboard.server.transport.lwm2m.security.cid.AbstractSecurityLwM2MIntegrationDtlsCidLength16Test;
+import org.thingsboard.server.transport.lwm2m.security.cid.AbstractSecurityLwM2MIntegrationDtlsCidLength4Test;
 
 import static org.thingsboard.server.common.data.device.credentials.lwm2m.LwM2MSecurityMode.NO_SEC;
 import static org.thingsboard.server.transport.lwm2m.Lwm2mTestHelper.LwM2MProfileBootstrapConfigType.NONE;
 
-public class NoSecLwM2MIntegrationDtlsCidLengthTest extends AbstractSecurityLwM2MIntegrationDtlsCidLength3Test {
+public class NoSecLwM2MIntegrationDtlsCidLengthTest extends AbstractSecurityLwM2MIntegrationDtlsCidLength16Test {
 
     @Before
     public void setUpNoSecDtlsCidLength() {
         transportConfiguration = getTransportConfiguration(OBSERVE_ATTRIBUTES_WITHOUT_PARAMS, getBootstrapServerCredentialsSecure(NO_SEC, NONE));
-        awaitAlias = "await on client state (NoSec_Lwm2m) DtlsCidLength = 3";
+        awaitAlias = "await on client state (NoSec_Lwm2m) serverDtlsCidLength = 16";
     }
 
     @Test
@@ -40,8 +41,23 @@ public class NoSecLwM2MIntegrationDtlsCidLengthTest extends AbstractSecurityLwM2
         testNoSecDtlsCidLength(0);
     }
 
+    @Test
+    public void testWithNoSecConnectLwm2mSuccessClientDtlsCidLength_1() throws Exception {
+        testNoSecDtlsCidLength(1);
+    }
+
     @Test
     public void testWithNoSecConnectLwm2mSuccessClientDtlsCidLength_2() throws Exception {
         testNoSecDtlsCidLength(2);
     }
+
+    @Test
+    public void testWithNoSecConnectLwm2mSuccessClientDtlsCidLength_4() throws Exception {
+        testNoSecDtlsCidLength(4);
+    }
+
+    @Test
+    public void testWithNoSecConnectLwm2mSuccessClientDtlsCidLength_16() throws Exception {
+        testNoSecDtlsCidLength(16);
+    }    
 }
diff --git a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_16/PskLwm2mIntegrationDtlsCidLengthTest.java b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_16/PskLwm2mIntegrationDtlsCidLengthTest.java
new file mode 100644
index 0000000000..579614d98e
--- /dev/null
+++ b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_16/PskLwm2mIntegrationDtlsCidLengthTest.java
@@ -0,0 +1,64 @@
+/**
+ * Copyright © 2016-2025 The Thingsboard Authors
+ *
+ * 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.thingsboard.server.transport.lwm2m.security.cid.serverDtlsCidLength_16;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.thingsboard.server.transport.lwm2m.security.cid.AbstractSecurityLwM2MIntegrationDtlsCidLength16Test;
+import org.thingsboard.server.transport.lwm2m.security.cid.AbstractSecurityLwM2MIntegrationDtlsCidLength4Test;
+
+import static org.thingsboard.server.common.data.device.credentials.lwm2m.LwM2MSecurityMode.PSK;
+import static org.thingsboard.server.transport.lwm2m.Lwm2mTestHelper.LwM2MProfileBootstrapConfigType.NONE;
+
+public class PskLwm2mIntegrationDtlsCidLengthTest extends AbstractSecurityLwM2MIntegrationDtlsCidLength16Test {
+
+    @Before
+    public void createProfileRpc() {
+        transportConfiguration = getTransportConfiguration(OBSERVE_ATTRIBUTES_WITHOUT_PARAMS, getBootstrapServerCredentialsSecure(PSK, NONE));
+        awaitAlias = "await on client state (Psk_Lwm2m) serverDtlsCidLength = 16";
+    }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_Null() throws Exception {
+        testPskDtlsCidLength(null);
+    }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_0() throws Exception {
+        testPskDtlsCidLength(0);
+    }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_1() throws Exception {
+        testPskDtlsCidLength(1);
+    }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_2() throws Exception {
+        testPskDtlsCidLength(2);
+    }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_4() throws Exception {
+        testPskDtlsCidLength(4);
+    }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_16() throws Exception {
+        testPskDtlsCidLength(16);
+    }
+}
+
diff --git a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_3/PskLwm2mIntegrationDtlsCidLengthTest.java b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_2/PskLwm2mIntegrationDtlsCidLengthTest.java
similarity index 73%
rename from application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_3/PskLwm2mIntegrationDtlsCidLengthTest.java
rename to application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_2/PskLwm2mIntegrationDtlsCidLengthTest.java
index 868a146ed7..2d68d057d8 100644
--- a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_3/PskLwm2mIntegrationDtlsCidLengthTest.java
+++ b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_2/PskLwm2mIntegrationDtlsCidLengthTest.java
@@ -13,21 +13,21 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package org.thingsboard.server.transport.lwm2m.security.cid.serverDtlsCidLength_3;
+package org.thingsboard.server.transport.lwm2m.security.cid.serverDtlsCidLength_2;
 
 import org.junit.Before;
 import org.junit.Test;
-import org.thingsboard.server.transport.lwm2m.security.cid.AbstractSecurityLwM2MIntegrationDtlsCidLength3Test;
+import org.thingsboard.server.transport.lwm2m.security.cid.AbstractSecurityLwM2MIntegrationDtlsCidLength2Test;
 
 import static org.thingsboard.server.common.data.device.credentials.lwm2m.LwM2MSecurityMode.PSK;
 import static org.thingsboard.server.transport.lwm2m.Lwm2mTestHelper.LwM2MProfileBootstrapConfigType.NONE;
 
-public class PskLwm2mIntegrationDtlsCidLengthTest extends AbstractSecurityLwM2MIntegrationDtlsCidLength3Test {
+public class PskLwm2mIntegrationDtlsCidLengthTest extends AbstractSecurityLwM2MIntegrationDtlsCidLength2Test {
 
     @Before
     public void createProfileRpc() {
         transportConfiguration = getTransportConfiguration(OBSERVE_ATTRIBUTES_WITHOUT_PARAMS, getBootstrapServerCredentialsSecure(PSK, NONE));
-        awaitAlias = "await on client state (Psk_Lwm2m) DtlsCidLength = 3";
+        awaitAlias = "await on client state (Psk_Lwm2m) serverDtlsCidLength = 2";
     }
 
     @Test
@@ -40,9 +40,24 @@ public class PskLwm2mIntegrationDtlsCidLengthTest extends AbstractSecurityLwM2MI
         testPskDtlsCidLength(0);
     }
 
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_1() throws Exception {
+        testPskDtlsCidLength(1);
+    }
+
     @Test
     public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_2() throws Exception {
         testPskDtlsCidLength(2);
     }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_4() throws Exception {
+        testPskDtlsCidLength(4);
+    }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_16() throws Exception {
+        testPskDtlsCidLength(16);
+    }
 }
 
diff --git a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_4/PskLwm2mIntegrationDtlsCidLengthTest.java b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_4/PskLwm2mIntegrationDtlsCidLengthTest.java
new file mode 100644
index 0000000000..6994e19fbf
--- /dev/null
+++ b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_4/PskLwm2mIntegrationDtlsCidLengthTest.java
@@ -0,0 +1,63 @@
+/**
+ * Copyright © 2016-2025 The Thingsboard Authors
+ *
+ * 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.thingsboard.server.transport.lwm2m.security.cid.serverDtlsCidLength_4;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.thingsboard.server.transport.lwm2m.security.cid.AbstractSecurityLwM2MIntegrationDtlsCidLength4Test;
+
+import static org.thingsboard.server.common.data.device.credentials.lwm2m.LwM2MSecurityMode.PSK;
+import static org.thingsboard.server.transport.lwm2m.Lwm2mTestHelper.LwM2MProfileBootstrapConfigType.NONE;
+
+public class PskLwm2mIntegrationDtlsCidLengthTest extends AbstractSecurityLwM2MIntegrationDtlsCidLength4Test {
+
+    @Before
+    public void createProfileRpc() {
+        transportConfiguration = getTransportConfiguration(OBSERVE_ATTRIBUTES_WITHOUT_PARAMS, getBootstrapServerCredentialsSecure(PSK, NONE));
+        awaitAlias = "await on client state (Psk_Lwm2m) serverDtlsCidLength = 4";
+    }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_Null() throws Exception {
+        testPskDtlsCidLength(null);
+    }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_0() throws Exception {
+        testPskDtlsCidLength(0);
+    }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_1() throws Exception {
+        testPskDtlsCidLength(1);
+    }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_2() throws Exception {
+        testPskDtlsCidLength(2);
+    }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_4() throws Exception {
+        testPskDtlsCidLength(4);
+    }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_16() throws Exception {
+        testPskDtlsCidLength(16);
+    }
+}
+
diff --git a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_null/NoSecLwM2MIntegrationDtlsCidLengthTest.java b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_null/NoSecLwM2MIntegrationDtlsCidLengthTest.java
index 9e7424743a..e85e03dfed 100644
--- a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_null/NoSecLwM2MIntegrationDtlsCidLengthTest.java
+++ b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_null/NoSecLwM2MIntegrationDtlsCidLengthTest.java
@@ -27,7 +27,7 @@ public class NoSecLwM2MIntegrationDtlsCidLengthTest extends AbstractSecurityLwM2
     @Before
     public void setUpNoSecDtlsCidLength() {
         transportConfiguration = getTransportConfiguration(OBSERVE_ATTRIBUTES_WITHOUT_PARAMS, getBootstrapServerCredentialsSecure(NO_SEC, NONE));
-        awaitAlias = "await on client state (NoSec_Lwm2m) DtlsCidLength = Null";
+        awaitAlias = "await on client state (NoSec_Lwm2m) serverDtlsCidLength = Null";
     }
 
     @Test
@@ -41,7 +41,22 @@ public class NoSecLwM2MIntegrationDtlsCidLengthTest extends AbstractSecurityLwM2
     }
 
     @Test
-    public void testWithNoSecConnectLwm2mSuccessClientDtlsCidLength_2() throws Exception {
-        testNoSecDtlsCidLength(2);
+    public void testWithNoSecConnectLwm2mSuccessClientDtlsCidLength_1() throws Exception {
+        testNoSecDtlsCidLength(1);
+    }
+
+    @Test
+    public void testWithNoSecConnectLwm2mSuccessClientDtlsCidLength_4() throws Exception {
+        testNoSecDtlsCidLength(4);
+    }
+
+    @Test
+    public void testWithNoSecConnectLwm2mSuccessClientDtlsCidLength_8() throws Exception {
+        testNoSecDtlsCidLength(8);
+    }
+
+    @Test
+    public void testWithNoSecConnectLwm2mSuccessClientDtlsCidLength_16() throws Exception {
+        testNoSecDtlsCidLength(16);
     }
 }
diff --git a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_null/PskLwm2mIntegrationDtlsCidLengthTest.java b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_null/PskLwm2mIntegrationDtlsCidLengthTest.java
index 8a8f01b3ab..e482e1b106 100644
--- a/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_null/PskLwm2mIntegrationDtlsCidLengthTest.java
+++ b/application/src/test/java/org/thingsboard/server/transport/lwm2m/security/cid/serverDtlsCidLength_null/PskLwm2mIntegrationDtlsCidLengthTest.java
@@ -27,7 +27,7 @@ public class PskLwm2mIntegrationDtlsCidLengthTest extends AbstractSecurityLwM2MI
     @Before
     public void createProfileRpc() {
         transportConfiguration = getTransportConfiguration(OBSERVE_ATTRIBUTES_WITHOUT_PARAMS, getBootstrapServerCredentialsSecure(PSK, NONE));
-        awaitAlias = "await on client state (Psk_Lwm2m) DtlsCidLength = Null";
+        awaitAlias = "await on client state (Psk_Lwm2m) serverDtlsCidLength = Null";
     }
 
     @Test
@@ -40,9 +40,24 @@ public class PskLwm2mIntegrationDtlsCidLengthTest extends AbstractSecurityLwM2MI
         testPskDtlsCidLength(0);
     }
 
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_1() throws Exception {
+        testPskDtlsCidLength(1);
+    }
+
     @Test
     public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_2() throws Exception {
         testPskDtlsCidLength(2);
     }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_4() throws Exception {
+        testPskDtlsCidLength(4);
+    }
+
+    @Test
+    public void testWithPskConnectLwm2mSuccessClientDtlsCidLength_16() throws Exception {
+        testPskDtlsCidLength(16);
+    }
 }
 
diff --git a/common/coap-server/src/main/java/org/thingsboard/server/coapserver/TbCoapDtlsSettings.java b/common/coap-server/src/main/java/org/thingsboard/server/coapserver/TbCoapDtlsSettings.java
index 56705b5608..f98dc7d3c6 100644
--- a/common/coap-server/src/main/java/org/thingsboard/server/coapserver/TbCoapDtlsSettings.java
+++ b/common/coap-server/src/main/java/org/thingsboard/server/coapserver/TbCoapDtlsSettings.java
@@ -66,7 +66,7 @@ public class TbCoapDtlsSettings {
     @Value("${coap.dtls.retransmission_timeout:9000}")
     private int dtlsRetransmissionTimeout;
 
-    @Value("${coap.dtls.connection_id_length:}")
+    @Value("${coap.dtls.connection_id_length:8}")
     private Integer cIdLength;
 
     @Value("${coap.dtls.max_transmission_unit:1024}")
diff --git a/common/transport/lwm2m/src/main/java/org/thingsboard/server/transport/lwm2m/config/LwM2MTransportServerConfig.java b/common/transport/lwm2m/src/main/java/org/thingsboard/server/transport/lwm2m/config/LwM2MTransportServerConfig.java
index c1af8f553a..bf65b95dd2 100644
--- a/common/transport/lwm2m/src/main/java/org/thingsboard/server/transport/lwm2m/config/LwM2MTransportServerConfig.java
+++ b/common/transport/lwm2m/src/main/java/org/thingsboard/server/transport/lwm2m/config/LwM2MTransportServerConfig.java
@@ -43,7 +43,7 @@ public class LwM2MTransportServerConfig implements LwM2MSecureServerConfig {
     private int dtlsRetransmissionTimeout;
 
     @Getter
-    @Value("${transport.lwm2m.dtls.connection_id_length:}")
+    @Value("${transport.lwm2m.dtls.connection_id_length:8}")
     private Integer dtlsCidLength;
 
     @Getter
diff --git a/transport/coap/src/main/resources/tb-coap-transport.yml b/transport/coap/src/main/resources/tb-coap-transport.yml
index f40a09c753..2f3942f847 100644
--- a/transport/coap/src/main/resources/tb-coap-transport.yml
+++ b/transport/coap/src/main/resources/tb-coap-transport.yml
@@ -193,7 +193,7 @@ coap:
     # - A value of 0 means we accept using CID but will not generate one for foreign peer (enables support but not for incoming traffic).
     # - A value between 0 and <= 4: SingleNodeConnectionIdGenerator is used
     # - A value that are > 4: MultiNodeConnectionIdGenerator is used
-    connection_id_length: "${COAP_DTLS_CONNECTION_ID_LENGTH:}"
+    connection_id_length: "${COAP_DTLS_CONNECTION_ID_LENGTH:8}"
     # Specify the MTU (Maximum Transmission Unit).
     # Should be used if LAN MTU is not used, e.g. if IP tunnels are used or if the client uses a smaller value than the LAN MTU.
     # Default = 1024
diff --git a/transport/lwm2m/src/main/resources/tb-lwm2m-transport.yml b/transport/lwm2m/src/main/resources/tb-lwm2m-transport.yml
index 0895bfa676..323f80b999 100644
--- a/transport/lwm2m/src/main/resources/tb-lwm2m-transport.yml
+++ b/transport/lwm2m/src/main/resources/tb-lwm2m-transport.yml
@@ -173,7 +173,7 @@ transport:
       # - A value of 0 means we accept using CID but will not generate one for foreign peer (enables support but not for incoming traffic).
       # - A value between 0 and <= 4: SingleNodeConnectionIdGenerator is used
       # - A value that are > 4: MultiNodeConnectionIdGenerator is used
-      connection_id_length: "${LWM2M_DTLS_CONNECTION_ID_LENGTH:}"
+      connection_id_length: "${LWM2M_DTLS_CONNECTION_ID_LENGTH:8}"
     server:
       # LwM2M Server ID
       id: "${LWM2M_SERVER_ID:123}"