diff --git a/include/logger.hpp b/include/logger.hpp
new file mode 100644
index 0000000..4bb2b48
--- /dev/null
+++ b/include/logger.hpp
@@ -0,0 +1,40 @@
+#pragma once
+
+#include <iostream>
+#include <fstream>
+#include <string>
+#include <ctime>
+#include <chrono>
+#include <iomanip>
+#include <sstream>
+
+enum class LogLevel
+{
+    INFO,
+    WARN,
+    ERROR
+};
+
+class Logger
+{
+public:
+    static void set_log_to_file(const std::string &filename);
+
+    static void log(LogLevel level, const std::string &msg);
+
+private:
+    static std::ofstream log_file;
+    static std::string current_log_filename;
+    static std::string get_time_string();
+
+    static void rotate_logs();
+    static size_t get_file_size(const std::string &filename);
+
+    static constexpr size_t MAX_LOG_FILE_SIZE = 10 * 1024 * 1024; // 10MB
+    static constexpr int MAX_LOG_BACKUP_COUNT = 5;
+};
+
+// 简化宏
+#define LOG_INFO(msg) Logger::log(LogLevel::INFO, msg)
+#define LOG_WARN(msg) Logger::log(LogLevel::WARN, msg)
+#define LOG_ERROR(msg) Logger::log(LogLevel::ERROR, msg)
diff --git a/include/mqtt_client.hpp b/include/mqtt_client.hpp
new file mode 100644
index 0000000..eeeef0f
--- /dev/null
+++ b/include/mqtt_client.hpp
@@ -0,0 +1,51 @@
+#pragma once
+
+#include <string>
+#include <functional>
+#include <memory>
+#include <atomic>
+#include <mutex>
+#include <mqtt/async_client.h>
+#include "mqtt_config.hpp"
+
+class MQTTClient : public virtual mqtt::callback
+{
+public:
+    using ConnectCallback = std::function<void()>;
+    using DisconnectCallback = std::function<void()>;
+    using MessageCallback = std::function<void(const std::string &topic, const std::string &message)>;
+
+    explicit MQTTClient(const MQTTConfig &config);
+    ~MQTTClient();
+
+    void setConnectCallback(ConnectCallback cb);
+    void setDisconnectCallback(DisconnectCallback cb);
+    void setMessageCallback(MessageCallback cb);
+
+    void connect();
+    void disconnect();
+    void publish(const std::string &topic, const std::string &payload, int qos = -1);
+    void subscribe(const std::string &topic, int qos = -1);
+    void switchServer(const MQTTConfig &newConfig);
+
+    bool isConnected() const;
+
+private:
+    void initializeClient();
+    void startReconnect();
+
+    // mqtt::callback 实现
+    void connection_lost(const std::string &cause) override;
+    void message_arrived(mqtt::const_message_ptr msg) override;
+    void delivery_complete(mqtt::delivery_token_ptr token) override {}
+
+    MQTTConfig config_;
+    std::shared_ptr<mqtt::async_client> client_;
+    std::atomic<bool> connected_;
+    std::atomic<bool> reconnect_active_;
+    std::mutex mutex_;
+
+    ConnectCallback on_connect_;
+    DisconnectCallback on_disconnect_;
+    MessageCallback on_message_;
+};
diff --git a/include/mqtt_client_wrapper.hpp b/include/mqtt_client_wrapper.hpp
new file mode 100644
index 0000000..c24a043
--- /dev/null
+++ b/include/mqtt_client_wrapper.hpp
@@ -0,0 +1,12 @@
+#pragma once
+
+#include "mqtt_config.hpp"
+#include "logger.hpp"
+#include "mqtt_client.hpp"
+
+// 启动 MQTT 客户端（内部自动连接、订阅、发布等）
+void mqtt_client_thread_func();
+
+// 外部可访问的 MQTT 客户端指针
+extern std::shared_ptr<MQTTClient> mqtt_client;
+extern std::atomic<bool> mqtt_restart_required;
\ No newline at end of file
diff --git a/include/mqtt_config.hpp b/include/mqtt_config.hpp
new file mode 100644
index 0000000..7a8167f
--- /dev/null
+++ b/include/mqtt_config.hpp
@@ -0,0 +1,55 @@
+#pragma once
+
+#include <string>
+#include <map>
+#include <fstream>
+#include <iostream>
+#include <nlohmann/json.hpp>
+#include <unistd.h>
+#include <limits.h>
+#include <stdexcept>
+#include "logger.hpp"
+
+using ordered_json = nlohmann::ordered_json;
+
+struct MQTTTopics
+{
+    std::string uplink_1;
+    std::string uplink_2;
+    std::string downlink;
+};
+
+struct MQTTPorts
+{
+    int config_port;
+    int uplink_1_port;
+    int uplink_2_port;
+    int downlink_port;
+};
+
+struct MQTTConfig
+{
+    std::string device_id;
+    std::string vin;
+    std::string server_ip;
+    int server_port;
+    std::string client_id;
+    std::string username;
+    std::string password;
+    int qos;
+    int keep_alive;
+    bool clean_session;
+    MQTTTopics topics;
+    MQTTPorts ports;
+
+    static MQTTConfig load_from_file(const std::string &filepath);
+    // 用完整 JSON 对象更新原始配置中已有字段
+    bool update_mqtt_config(const ordered_json &new_values,
+                            const std::string &filepath = "config.json");
+};
+
+std::string get_executable_dir();
+std::string get_executable_dir_file_path(const std::string &filename);
+
+// 全局配置变量
+extern MQTTConfig g_mqtt_config;
diff --git a/src/logger.cpp b/src/logger.cpp
new file mode 100644
index 0000000..acecf7c
--- /dev/null
+++ b/src/logger.cpp
@@ -0,0 +1,101 @@
+#include "logger.hpp"
+#include <iomanip>
+#include <ctime>
+#include <fstream>
+#include <cstdio>
+
+std::ofstream Logger::log_file;
+std::string Logger::current_log_filename;
+
+void Logger::set_log_to_file(const std::string &filename)
+{
+    current_log_filename = filename;
+    log_file.open(filename, std::ios::app);
+    if (!log_file.is_open())
+    {
+        std::cerr << "[Logger] Failed to open log file: " << filename << std::endl;
+    }
+}
+
+std::string Logger::get_time_string()
+{
+    using namespace std::chrono;
+
+    // 获取当前时间点
+    auto now = system_clock::now();
+    auto ms = duration_cast<milliseconds>(now.time_since_epoch()) % 1000;
+
+    // 转换为 time_t（秒）
+    auto t = system_clock::to_time_t(now);
+    std::tm ltm = *std::localtime(&t);
+
+    // 拼接格式化字符串
+    std::ostringstream oss;
+    oss << std::put_time(&ltm, "%Y-%m-%d %H:%M:%S")
+        << '.' << std::setw(3) << std::setfill('0') << ms.count();
+
+    return oss.str();
+}
+
+void Logger::log(LogLevel level, const std::string &msg)
+{
+    std::string level_str;
+    switch (level)
+    {
+    case LogLevel::INFO:
+        level_str = "[INFO] ";
+        break;
+    case LogLevel::WARN:
+        level_str = "[WARN] ";
+        break;
+    case LogLevel::ERROR:
+        level_str = "[ERROR]";
+        break;
+    }
+
+    std::string full_msg = get_time_string() + " " + level_str + " " + msg;
+
+    std::cout << full_msg << std::endl;
+
+    if (log_file.is_open())
+    {
+        log_file << full_msg << std::endl;
+        log_file.flush();
+
+        // 检查是否需要轮转
+        if (get_file_size(current_log_filename) >= MAX_LOG_FILE_SIZE)
+        {
+            rotate_logs();
+        }
+    }
+}
+
+size_t Logger::get_file_size(const std::string &filename)
+{
+    std::ifstream in(filename, std::ifstream::ate | std::ifstream::binary);
+    return in.is_open() ? static_cast<size_t>(in.tellg()) : 0;
+}
+
+void Logger::rotate_logs()
+{
+    log_file.close();
+
+    // 删除最旧的日志
+    std::string oldest = current_log_filename + "." + std::to_string(MAX_LOG_BACKUP_COUNT);
+    std::remove(oldest.c_str());
+
+    // 重命名 *.4 -> *.5, ..., *.1 -> *.2
+    for (int i = MAX_LOG_BACKUP_COUNT - 1; i >= 1; --i)
+    {
+        std::string old_name = current_log_filename + "." + std::to_string(i);
+        std::string new_name = current_log_filename + "." + std::to_string(i + 1);
+        std::rename(old_name.c_str(), new_name.c_str());
+    }
+
+    // 当前日志 -> .1
+    std::string first_backup = current_log_filename + ".1";
+    std::rename(current_log_filename.c_str(), first_backup.c_str());
+
+    // 重新打开新日志
+    log_file.open(current_log_filename, std::ios::trunc);
+}
diff --git a/src/mqtt_client.cpp b/src/mqtt_client.cpp
new file mode 100644
index 0000000..83ca99a
--- /dev/null
+++ b/src/mqtt_client.cpp
@@ -0,0 +1,168 @@
+#include "mqtt_client.hpp"
+#include <iostream>
+#include <thread>
+#include <chrono>
+
+MQTTClient::MQTTClient(const MQTTConfig &config)
+    : config_(config), connected_(false), reconnect_active_(false)
+{
+    initializeClient();
+}
+
+MQTTClient::~MQTTClient()
+{
+    disconnect();
+}
+
+void MQTTClient::initializeClient()
+{
+    std::string address = "tcp://" + config_.server_ip + ":" + std::to_string(config_.server_port);
+    client_ = std::make_shared<mqtt::async_client>(address, config_.client_id);
+    client_->set_callback(*this);
+}
+
+void MQTTClient::connect()
+{
+    std::lock_guard<std::mutex> lock(mutex_);
+    if (connected_)
+        return;
+
+    try
+    {
+        auto connOpts = mqtt::connect_options_builder()
+                            .clean_session(config_.clean_session)
+                            .automatic_reconnect(true)
+                            .keep_alive_interval(std::chrono::seconds(config_.keep_alive))
+                            .user_name(config_.username)
+                            .password(config_.password)
+                            .finalize();
+
+        client_->connect(connOpts)->wait();
+        connected_ = true;
+        reconnect_active_ = false;
+
+        if (on_connect_)
+            on_connect_();
+    }
+    catch (const mqtt::exception &e)
+    {
+        std::cerr << "[MQTTClient] Connect failed: " << e.what() << std::endl;
+        startReconnect();
+    }
+}
+
+void MQTTClient::disconnect()
+{
+    std::lock_guard<std::mutex> lock(mutex_);
+    if (!connected_)
+        return;
+
+    try
+    {
+        client_->disconnect()->wait();
+        connected_ = false;
+        if (on_disconnect_)
+            on_disconnect_();
+    }
+    catch (const mqtt::exception &e)
+    {
+        std::cerr << "[MQTTClient] Disconnect failed: " << e.what() << std::endl;
+    }
+}
+
+void MQTTClient::publish(const std::string &topic, const std::string &payload, int qos)
+{
+    if (qos == -1)
+        qos = config_.qos;
+
+    try
+    {
+        client_->publish(topic, payload.data(), payload.size(), qos, false)->wait_for(std::chrono::milliseconds(500));
+    }
+    catch (const mqtt::exception &e)
+    {
+        std::cerr << "[MQTTClient] Publish failed: " << e.what() << std::endl;
+        if (!connected_)
+            startReconnect();
+    }
+}
+
+void MQTTClient::subscribe(const std::string &topic, int qos)
+{
+    if (qos == -1)
+        qos = config_.qos;
+
+    try
+    {
+        client_->subscribe(topic, qos)->wait();
+    }
+    catch (const mqtt::exception &e)
+    {
+        std::cerr << "[MQTTClient] Subscribe failed: " << e.what() << std::endl;
+        if (!connected_)
+            startReconnect();
+    }
+}
+
+void MQTTClient::switchServer(const MQTTConfig &newConfig)
+{
+    std::lock_guard<std::mutex> lock(mutex_);
+    if (connected_)
+    {
+        try
+        {
+            client_->disconnect()->wait();
+        }
+        catch (...)
+        {
+        }
+        connected_ = false;
+    }
+    config_ = newConfig;
+    initializeClient();
+    connect();
+}
+
+void MQTTClient::startReconnect()
+{
+    if (reconnect_active_)
+        return;
+    reconnect_active_ = true;
+
+    std::thread([this]
+                {
+        while (!connected_ && reconnect_active_) {
+            std::this_thread::sleep_for(std::chrono::seconds(2));
+            try {
+                connect();
+            } catch (...) {}
+        }
+        reconnect_active_ = false; })
+        .detach();
+}
+
+void MQTTClient::connection_lost(const std::string &cause)
+{
+    std::lock_guard<std::mutex> lock(mutex_);
+    connected_ = false;
+    if (on_disconnect_)
+        on_disconnect_();
+    startReconnect();
+}
+
+void MQTTClient::message_arrived(mqtt::const_message_ptr msg)
+{
+    if (on_message_)
+    {
+        on_message_(msg->get_topic(), msg->get_payload_str());
+    }
+}
+
+bool MQTTClient::isConnected() const
+{
+    return connected_;
+}
+
+void MQTTClient::setConnectCallback(ConnectCallback cb) { on_connect_ = cb; }
+void MQTTClient::setDisconnectCallback(DisconnectCallback cb) { on_disconnect_ = cb; }
+void MQTTClient::setMessageCallback(MessageCallback cb) { on_message_ = cb; }
diff --git a/src/mqtt_client_wrapper.cpp b/src/mqtt_client_wrapper.cpp
new file mode 100644
index 0000000..9640d90
--- /dev/null
+++ b/src/mqtt_client_wrapper.cpp
@@ -0,0 +1,57 @@
+#include "mqtt_client_wrapper.hpp"
+
+std::shared_ptr<MQTTClient> mqtt_client;
+std::atomic<bool> mqtt_restart_required{false};
+
+static uint16_t broadcast_sequence = 0;
+
+// MQTT 回调定义
+static void on_mqtt_connected()
+{
+    LOG_INFO("[MQTT] Connected to broker.");
+    mqtt_client->subscribe(g_mqtt_config.topics.downlink);
+}
+
+static void on_mqtt_disconnected()
+{
+    LOG_WARN("[MQTT] Disconnected from broker.");
+}
+
+static void on_mqtt_message_received(const std::string &topic, const std::string &message)
+{
+    LOG_INFO("[MQTT] Received message on topic [" + topic + "], len = " + std::to_string(message.size()));
+
+    try
+    {
+    }
+    catch (const std::exception &e)
+    {
+        LOG_ERROR(std::string("[MQTT] Failed to process incoming JSON: ") + e.what());
+    }
+}
+
+void mqtt_client_thread_func()
+{
+    while (true)
+    {
+        const auto &cfg = g_mqtt_config;
+        mqtt_client = std::make_unique<MQTTClient>(cfg);
+        mqtt_client->setConnectCallback(on_mqtt_connected);
+        mqtt_client->setDisconnectCallback(on_mqtt_disconnected);
+        mqtt_client->setMessageCallback(on_mqtt_message_received);
+
+        mqtt_client->connect();
+
+        // 主线程监听重启信号
+        while (!mqtt_restart_required)
+        {
+            std::this_thread::sleep_for(std::chrono::seconds(1));
+        }
+
+        // 需要重启
+        LOG_INFO("[MQTT] Restarting client...");
+        mqtt_client->disconnect(); // 可加锁
+        mqtt_client.reset();
+        mqtt_restart_required = false;
+    }
+}
diff --git a/src/mqtt_config.cpp b/src/mqtt_config.cpp
new file mode 100644
index 0000000..6482170
--- /dev/null
+++ b/src/mqtt_config.cpp
@@ -0,0 +1,122 @@
+#include "mqtt_config.hpp"
+
+MQTTConfig g_mqtt_config;
+
+MQTTConfig MQTTConfig::load_from_file(const std::string &filepath)
+{
+    MQTTConfig cfg;
+
+    std::ifstream ifs(filepath);
+    if (!ifs)
+    {
+        LOG_ERROR("[Config] Failed to open config file: " + filepath);
+        throw std::runtime_error("Failed to open config file: " + filepath);
+    }
+
+    nlohmann::json j;
+    ifs >> j;
+
+    cfg.device_id = j["device_id"];
+    cfg.vin = j["vin"];
+    cfg.server_ip = j["server_ip"];
+    cfg.server_port = j["server_port"];
+    cfg.client_id = j["client_id"];
+    cfg.username = j["username"];
+    cfg.password = j["password"];
+    cfg.qos = j["qos"];
+    cfg.keep_alive = j["keep_alive"];
+    cfg.clean_session = j["clean_session"];
+
+    const std::string &id = cfg.device_id;
+    cfg.topics.uplink_1 = j["topics"]["uplink_1"].get<std::string>() + id;
+    cfg.topics.uplink_2 = j["topics"]["uplink_2"].get<std::string>() + id;
+    cfg.topics.downlink = j["topics"]["downlink"].get<std::string>() + id;
+
+    cfg.ports.config_port = j["ports"]["config_port"];
+    cfg.ports.uplink_1_port = j["ports"]["uplink_1_port"];
+    cfg.ports.uplink_2_port = j["ports"]["uplink_2_port"];
+    cfg.ports.downlink_port = j["ports"]["downlink_port"];
+
+    LOG_INFO("[Config] Loaded config from " + filepath);
+    LOG_INFO("  - MQTT Server: " + cfg.server_ip + ":" + std::to_string(cfg.server_port));
+    LOG_INFO("  - Client ID: " + cfg.client_id);
+    LOG_INFO("  - Topics: " + cfg.topics.uplink_1 + ", " + cfg.topics.uplink_2 + ", " + cfg.topics.downlink);
+
+    return cfg;
+}
+
+bool MQTTConfig::update_mqtt_config(const ordered_json &new_values,
+                                    const std::string &filepath)
+{
+    std::ifstream ifs(filepath);
+    if (!ifs.is_open())
+    {
+        LOG_ERROR("[ConfigEdit] Failed to open config file: " + filepath);
+        return false;
+    }
+
+    ordered_json j;
+    try
+    {
+        ifs >> j;
+        ifs.close();
+    }
+    catch (const std::exception &e)
+    {
+        LOG_ERROR(std::string("[ConfigEdit] JSON parse error: ") + e.what());
+        return false;
+    }
+
+    for (auto it = new_values.begin(); it != new_values.end(); ++it)
+    {
+        const std::string &key = it.key();
+        const auto &val = it.value();
+
+        if (j.contains(key))
+        {
+            LOG_INFO("[ConfigEdit] Updating key: " + key + " -> " + val.dump());
+            j[key] = val;
+        }
+        else
+        {
+            LOG_WARN("[ConfigEdit] Warning: key '" + key + "' not found in config, ignored.");
+        }
+    }
+
+    std::ofstream ofs(filepath);
+    if (!ofs.is_open())
+    {
+        LOG_ERROR("[ConfigEdit] Failed to write updated config file: " + filepath);
+        return false;
+    }
+
+    ofs << j.dump(4);
+    ofs.close();
+    return true;
+}
+
+std::string get_executable_dir()
+{
+    char result[PATH_MAX] = {0};
+    ssize_t count = readlink("/proc/self/exe", result, PATH_MAX);
+    if (count == -1)
+    {
+        throw std::runtime_error("Failed to read /proc/self/exe");
+    }
+
+    std::string full_path(result, count);
+    auto pos = full_path.find_last_of('/');
+    if (pos == std::string::npos)
+    {
+        throw std::runtime_error("Failed to find executable directory");
+    }
+    return full_path.substr(0, pos);
+}
+
+std::string get_executable_dir_file_path(const std::string &filename)
+{
+    std::string dir = get_executable_dir();
+    if (dir.back() != '/')
+        dir += '/';
+    return dir + filename;
+}
\ No newline at end of file