diff --git a/broker/src/main/java/io/moquette/spi/impl/ProtocolProcessor.java b/broker/src/main/java/io/moquette/spi/impl/ProtocolProcessor.java
index 8b7f7c9f..a1fa82d4 100755
--- a/broker/src/main/java/io/moquette/spi/impl/ProtocolProcessor.java
+++ b/broker/src/main/java/io/moquette/spi/impl/ProtocolProcessor.java
@@ -188,8 +188,7 @@ public class ProtocolProcessor {
         String clientId = payload.clientIdentifier();
         LOG.info("Processing CONNECT message. CId={}, username={}", clientId, payload.userName());
 
-        if (msg.variableHeader().version() < MqttVersion.MQTT_3_1_1.protocolLevel() ||
-                msg.variableHeader().version() >= MqttVersion.Wildfire_Max.protocolLevel()) {
+        if (msg.variableHeader().version() < MqttVersion.MQTT_3_1_1.protocolLevel()) {
             MqttConnAckMessage badProto = connAck(CONNECTION_REFUSED_UNACCEPTABLE_PROTOCOL_VERSION);
 
             LOG.error("MQTT protocol version is not valid. CId={}", clientId);
diff --git a/broker/src/main/java/io/netty/handler/codec/mqtt/MqttVersion.java b/broker/src/main/java/io/netty/handler/codec/mqtt/MqttVersion.java
index 9d5b7ed6..b92c3764 100755
--- a/broker/src/main/java/io/netty/handler/codec/mqtt/MqttVersion.java
+++ b/broker/src/main/java/io/netty/handler/codec/mqtt/MqttVersion.java
@@ -27,7 +27,7 @@ public enum MqttVersion {
     MQTT_3_1_1("MQTT", (byte) 4),
     Wildfire_1("MQTT", (byte) 5),
     Wildfire_2("MQTT", (byte) 6),
-    Wildfire_Max("MQTT", (byte) 7);
+    Wildfire_Future("MQTT", (byte) 7);
 
     private final String name;
     private final byte level;
@@ -59,6 +59,9 @@ public enum MqttVersion {
                 }
             }
         }
+        if(protocolLevel > Wildfire_Future.level) {
+            return Wildfire_Future;
+        }
         throw new MqttUnacceptableProtocolVersionException(protocolName + "is unknown protocol name");
     }
 
@@ -68,6 +71,9 @@ public enum MqttVersion {
                 return mv;
             }
         }
+        if(protocolLevel > Wildfire_Future.level) {
+            return Wildfire_Future;
+        }
         throw new MqttUnacceptableProtocolVersionException(protocolLevel + "is unknown protocol level");
     }
 }