MQTT Broker(Mosquitto) - ESP32

--Resource --

1. ESP8266 code

    #include <ESP8266WiFi.h>
    #include <PubSubClient.h>
         
        const char* ssid = "YourNetworkName";
        const char* password =  "YourNetworkPassword";
        const char* mqttServer = "m11.cloudmqtt.com";
        const int mqttPort = 12948;
        const char* mqttUser = "YourMqttUser";
        const char* mqttPassword = "YourMqttUserPassword";
         
        WiFiClient espClient;
        PubSubClient client(espClient);
         
        void setup() {
         
          Serial.begin(115200);
         
          WiFi.begin(ssid, password);
         
          while (WiFi.status() != WL_CONNECTED) {
            delay(500);
            Serial.println("Connecting to WiFi..");
          }
          Serial.println("Connected to the WiFi network");
         
          client.setServer(mqttServer, mqttPort);
          client.setCallback(callback);
         
          while (!client.connected()) {
            Serial.println("Connecting to MQTT...");
         
            if (client.connect("ESP8266Client", mqttUser, mqttPassword )) {
         
              Serial.println("connected");  
         
            } else {
         
              Serial.print("failed with state ");
              Serial.print(client.state());
              delay(2000);
         
            }
          }
         
          client.publish("esp/test", "Hello from ESP8266");
          client.subscribe("esp/test");
         
        }
         
        void callback(char* topic, byte* payload, unsigned int length) {
         
          Serial.print("Message arrived in topic: ");
          Serial.println(topic);
         
          Serial.print("Message:");
          for (int i = 0; i < length; i++) {
            Serial.print((char)payload[i]);
          }
         
          Serial.println();
          Serial.println("-----------------------");
         
        }
         
        void loop() {
          client.loop();
        }

2. ESP32 code

    #include <WiFi.h>
    #include <PubSubClient.h>
        
        const char* ssid = "wifi ssid";
        const char* password =  "wifi password";
        const char* mqttServer = "192.168.1.4"; // local ip address
        const int mqttPort = 1883;
        const char* mqttUser = "mqqtt_user that configured on mosquitto";
        const char* mqttPassword = "mqqtt_password for mqtt_user that configured on mosquitto";
        
        WiFiClient espClient;
        PubSubClient client(espClient);
        
        void setup() {
          WiFi.mode(WIFI_STA);
          Serial.begin(115200);
          WiFi.begin(ssid, password);
        
          while (WiFi.status() != WL_CONNECTED) {
            delay(500);
            Serial.println("Connecting to WiFi..");
          }
        
          Serial.println("Connected to the WiFi network");
        
          client.setServer(mqttServer, mqttPort);
        
          while (!client.connected()) {
            Serial.println("Connecting to MQTT...");
        
            if (client.connect("arduinoClient",mqttUser,mqttPassword)) {
        
              Serial.println("connected");
        
            } else {
        
              Serial.print("failed with state ");
              Serial.print(client.state());
              delay(2000);
        
            }
          }
        
          client.publish("esp/test", "Hello from ESP32");
        
        }
        
        void loop() {
          client.publish("esp/test", "Hello from ESP32");
          delay(5000);
          client.loop();
        }