diff --git a/.vscode/settings.json b/.vscode/settings.json
index 6cd35a4..ebb2564 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -155,6 +155,8 @@
         "qtablewidget": "cpp",
         "qapplication": "cpp",
         "text_encoding": "cpp",
-        "hash_map": "cpp"
+        "hash_map": "cpp",
+        "qreadwritelock": "cpp",
+        "qdatastream": "cpp"
     }
 }
\ No newline at end of file
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 742bdf2..ff07d17 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -26,4 +26,5 @@ set(LIBRARY_OUTPUT_PATH ${PROJECT_BINARY_DIR}/lib/${CMAKE_BUILD_TYPE})
 set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${PROJECT_BINARY_DIR}/bin/${CMAKE_BUILD_TYPE}/) 
 
 add_subdirectory(Protocol)
+add_subdirectory(Server)
 add_subdirectory(Test)
diff --git a/Protocol/CMakeLists.txt b/Protocol/CMakeLists.txt
index 797d0f4..20266dd 100644
--- a/Protocol/CMakeLists.txt
+++ b/Protocol/CMakeLists.txt
@@ -15,6 +15,9 @@ find_package(Qt${QT_VERSION_MAJOR} REQUIRED COMPONENTS Core)
 set(SOURCES
 Protocol.cxx
 Protocol.h
+InfoClient.h
+InfoClient.cpp
+InfoPack.hpp
 )
 
 add_library(Protocol STATIC ${SOURCES})
diff --git a/Protocol/InfoClient.cpp b/Protocol/InfoClient.cpp
new file mode 100644
index 0000000..8e5496a
--- /dev/null
+++ b/Protocol/InfoClient.cpp
@@ -0,0 +1,13 @@
+#include "InfoClient.h"
+
+QDataStream& operator<<(QDataStream& data, const InfoClient& info)
+{
+    info.serialize(data);
+    return data;
+}
+
+QDataStream& operator>>(QDataStream& data, InfoClient& info)
+{
+    info.deserialize(data);
+    return data;
+}
diff --git a/Protocol/InfoClient.h b/Protocol/InfoClient.h
new file mode 100644
index 0000000..0072c65
--- /dev/null
+++ b/Protocol/InfoClient.h
@@ -0,0 +1,49 @@
+#ifndef COMSTRUCT_H
+#define COMSTRUCT_H
+
+#include <QBuffer>
+#include <QDataStream>
+#include <QIODevice>
+#include <QString>
+#include <QVector>
+
+struct InfoClient {
+    QString id;
+    QString name;
+
+    void serialize(QDataStream& data) const
+    {
+        data << id << name;
+    }
+
+    void deserialize(QDataStream& data)
+    {
+        data >> id >> name;
+    }
+};
+
+QDataStream& operator<<(QDataStream& data, const InfoClient& info);
+QDataStream& operator>>(QDataStream& data, InfoClient& info);
+
+struct InfoClientVec {
+    QVector<InfoClient> vec;
+
+    void serialize(QDataStream& data) const
+    {
+        data << vec.size();
+        for (const auto& info : vec) {
+            data << info;
+        }
+    }
+    void deserialize(QDataStream& data)
+    {
+        qsizetype size;
+        data >> size;
+        vec.resize(size);
+        for (quint32 i = 0; i < size; ++i) {
+            data >> vec[i];
+        }
+    }
+};
+
+#endif   // COMSTRUCT_H
\ No newline at end of file
diff --git a/Protocol/InfoPack.hpp b/Protocol/InfoPack.hpp
new file mode 100644
index 0000000..92b53dc
--- /dev/null
+++ b/Protocol/InfoPack.hpp
@@ -0,0 +1,25 @@
+#ifndef INFO_PACK_HPP
+#define INFO_PACK_HPP
+
+#include <QByteArray>
+#include <QDataStream>
+#include <QDebug>
+
+template <typename T> QByteArray infoPack(const T& obj)
+{
+    QByteArray byteArray;
+    QDataStream stream(&byteArray, QIODevice::ReadWrite);
+    obj.serialize(stream);
+    stream.device()->seek(0);
+    return byteArray;
+}
+
+template <typename T> T infoUnpack(const QByteArray& byteArray)
+{
+    T obj;
+    QDataStream stream(byteArray);
+    obj.deserialize(stream);
+    return obj;
+}
+
+#endif   // INFO_PACK_HPP
\ No newline at end of file
diff --git a/Server/CMakeLists.txt b/Server/CMakeLists.txt
new file mode 100644
index 0000000..e546675
--- /dev/null
+++ b/Server/CMakeLists.txt
@@ -0,0 +1,17 @@
+cmake_minimum_required(VERSION 3.16)
+
+project(frelayServer LANGUAGES CXX)
+
+set(CMAKE_AUTOUIC ON)
+set(CMAKE_AUTOMOC ON)
+set(CMAKE_AUTORCC ON)
+
+set(CMAKE_CXX_STANDARD 11)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+
+find_package(QT NAMES Qt6 Qt5 REQUIRED COMPONENTS Core Network)
+find_package(Qt${QT_VERSION_MAJOR} REQUIRED COMPONENTS Core Network)
+
+add_executable(frelayServer Server.h Server.cpp main.cpp)
+target_link_libraries(frelayServer PRIVATE Protocol)
+target_link_libraries(frelayServer PRIVATE Qt${QT_VERSION_MAJOR}::Core Qt${QT_VERSION_MAJOR}::Network)
\ No newline at end of file
diff --git a/Server/Server.cpp b/Server/Server.cpp
new file mode 100644
index 0000000..9692142
--- /dev/null
+++ b/Server/Server.cpp
@@ -0,0 +1,221 @@
+#include "Server.h"
+
+#include <QDateTime>
+#include <QDebug>
+
+#include "InfoClient.h"
+#include "InfoPack.hpp"
+
+Server::Server(QObject* parent) : QTcpServer(parent)
+{
+    monitorTimer_ = new QTimer(this);
+    connect(monitorTimer_, &QTimer::timeout, this, &Server::monitorClients);
+}
+
+Server::~Server()
+{
+    stopServer();
+}
+
+bool Server::startServer(quint16 port)
+{
+    if (!listen(QHostAddress::Any, port)) {
+        qWarning() << "Server start failed:" << errorString();
+        return false;
+    }
+
+    qDebug() << "Server started on port" << serverPort();
+    monitorTimer_->start(30000);
+    return true;
+}
+
+void Server::stopServer()
+{
+    monitorTimer_->stop();
+    close();
+
+    QWriteLocker locker(&rwLock_);
+    for (auto& client : clients_) {
+        client->socket->disconnectFromHost();
+        client->socket->deleteLater();
+    }
+    clients_.clear();
+}
+
+void Server::onNewConnection()
+{
+    QTcpSocket* clientSocket = nextPendingConnection();
+    QString clientId = QString("%1:%2").arg(clientSocket->peerAddress().toString()).arg(clientSocket->peerPort());
+
+    if (clients_.size() >= 100) {
+        qWarning() << "Client connection refused (max limit reached):" << clientId;
+        clientSocket->disconnectFromHost();
+        return;
+    }
+
+    auto client = QSharedPointer<ClientInfo>::create();
+    client->socket = clientSocket;
+    client->id = clientId;
+    client->connectTime = QDateTime::currentSecsSinceEpoch();
+
+    connect(clientSocket, &QTcpSocket::readyRead, this, &Server::onReadyRead);
+    connect(clientSocket, &QTcpSocket::disconnected, this, &Server::onClientDisconnected);
+
+    {
+        QWriteLocker locker(&rwLock_);
+        clients_.insert(clientId, client);
+    }
+
+    qDebug() << "Client connected:" << clientId;
+    auto frame = QSharedPointer<FrameBuffer>::create();
+    frame->type = FBT_SER_MSG_YOURID;
+    frame->fid = "server";
+    frame->tid = clientId;
+    frame->data = QString("Welcome client %1").arg(clientId).toUtf8();
+    sendData(clientSocket, frame);
+}
+
+void Server::onClientDisconnected()
+{
+    QTcpSocket* socket = qobject_cast<QTcpSocket*>(sender());
+    if (!socket) {
+        return;
+    }
+
+    QString clientId = QString("%1:%2").arg(socket->peerAddress().toString()).arg(socket->peerPort());
+
+    {
+        QWriteLocker locker(&rwLock_);
+        clients_.remove(clientId);
+    }
+
+    qDebug() << "Client disconnected:" << clientId;
+    socket->deleteLater();
+}
+
+void Server::onReadyRead()
+{
+    QTcpSocket* socket = qobject_cast<QTcpSocket*>(sender());
+    if (!socket) {
+        return;
+    }
+
+    QString clientId = QString("%1:%2").arg(socket->peerAddress().toString()).arg(socket->peerPort());
+
+    QSharedPointer<ClientInfo> client;
+    {
+        QReadLocker locker(&rwLock_);
+        client = clients_.value(clientId);
+    }
+
+    if (client) {
+        client->buffer.append(socket->readAll());
+        processClientData(client);
+    }
+}
+
+void Server::processClientData(QSharedPointer<ClientInfo> client)
+{
+    while (true) {
+        auto frame = Protocol::ParseBuffer(client->buffer);
+        if (frame.isNull()) {
+            break;
+        }
+        frame->fid = client->id;
+
+        if (frame->type <= 30) {
+            frame->tid = "server";
+            replyRequest(client, frame);
+        } else {
+            if (!forwardData(client, frame)) {
+                qWarning() << "Failed to forward data from" << client->id << "to" << frame->tid;
+            }
+        }
+    }
+}
+
+bool Server::forwardData(QSharedPointer<ClientInfo> client, QSharedPointer<FrameBuffer> frame)
+{
+    QSharedPointer<ClientInfo> targetClient;
+    {
+        QReadLocker locker(&rwLock_);
+        targetClient = clients_.value(frame->tid);
+    }
+
+    if (targetClient) {
+        return sendData(targetClient->socket, frame);
+    } else {
+        auto errorFrame = QSharedPointer<FrameBuffer>::create();
+        errorFrame->type = FBT_SER_MSG_FORWARD_FAILED;
+        errorFrame->fid = "server";
+        errorFrame->tid = client->id;
+        errorFrame->data = QString("Target client %1 not found").arg(frame->tid).toUtf8();
+        return sendData(client->socket, errorFrame);
+    }
+}
+
+void Server::replyRequest(QSharedPointer<ClientInfo> client, QSharedPointer<FrameBuffer> frame)
+{
+    switch (frame->type) {
+    case FBT_SER_MSG_ASKCLIENTS: {
+        QByteArray clientList = getClients();
+        auto replyFrame = QSharedPointer<FrameBuffer>::create();
+        replyFrame->type = FBT_SER_MSG_RESPONSE;
+        replyFrame->fid = "server";
+        replyFrame->tid = client->id;
+        replyFrame->data = clientList;
+        sendData(client->socket, replyFrame);
+        break;
+    }
+    default:
+        qWarning() << "Unknown request type:" << frame->type;
+        break;
+    }
+}
+
+bool Server::sendData(QTcpSocket* socket, QSharedPointer<FrameBuffer> frame)
+{
+    if (!socket || !socket->isOpen() || frame.isNull()) {
+        return false;
+    }
+
+    QByteArray data = Protocol::PackBuffer(frame);
+    if (data.isEmpty()) {
+        return false;
+    }
+
+    return socket->write(data) == data.size();
+}
+
+void Server::monitorClients()
+{
+    qint64 now = QDateTime::currentSecsSinceEpoch();
+    QWriteLocker locker(&rwLock_);
+
+    for (auto it = clients_.begin(); it != clients_.end();) {
+        if (now - it.value()->connectTime > 300) {
+            qDebug() << "Disconnecting inactive client:" << it.value()->id;
+            it.value()->socket->disconnectFromHost();
+            it = clients_.erase(it);
+        } else {
+            ++it;
+        }
+    }
+}
+
+QByteArray Server::getClients()
+{
+    InfoClientVec infoClients;
+
+    {
+        QReadLocker locker(&rwLock_);
+        for (auto& c : clients_) {
+            InfoClient infoClient;
+            infoClient.id = c->id;
+            infoClients.vec.append(infoClient);
+        }
+    }
+
+    auto ret = infoPack<InfoClientVec>(infoClients);
+    return ret;
+}
diff --git a/Server/Server.h b/Server/Server.h
new file mode 100644
index 0000000..304b9cf
--- /dev/null
+++ b/Server/Server.h
@@ -0,0 +1,50 @@
+// Server.h
+#ifndef SERVER_H
+#define SERVER_H
+
+#include <QMap>
+#include <QReadWriteLock>
+#include <QTcpServer>
+#include <QTcpSocket>
+#include <QTimer>
+
+#include "Protocol.h"
+
+class Server : public QTcpServer
+{
+    Q_OBJECT
+public:
+    explicit Server(QObject* parent = nullptr);
+    ~Server();
+
+    bool startServer(quint16 port);
+    void stopServer();
+
+private slots:
+    void onNewConnection();
+    void onClientDisconnected();
+    void onReadyRead();
+    void monitorClients();
+
+private:
+    QByteArray getClients();
+
+private:
+    struct ClientInfo {
+        QTcpSocket* socket;
+        QString id;
+        qint64 connectTime;
+        QByteArray buffer;
+    };
+
+    void processClientData(QSharedPointer<ClientInfo> client);
+    bool forwardData(QSharedPointer<ClientInfo> client, QSharedPointer<FrameBuffer> frame);
+    void replyRequest(QSharedPointer<ClientInfo> client, QSharedPointer<FrameBuffer> frame);
+    bool sendData(QTcpSocket* socket, QSharedPointer<FrameBuffer> frame);
+
+    QMap<QString, QSharedPointer<ClientInfo>> clients_;
+    QReadWriteLock rwLock_;
+    QTimer* monitorTimer_;
+};
+
+#endif   // SERVER_H
\ No newline at end of file
diff --git a/Server/main.cpp b/Server/main.cpp
new file mode 100644
index 0000000..b508d0c
--- /dev/null
+++ b/Server/main.cpp
@@ -0,0 +1,17 @@
+#include <QCoreApplication>
+
+#include "Server.h"
+
+int main(int argc, char* argv[])
+{
+    QCoreApplication app(argc, argv);
+
+    Server server;
+    if (!server.startServer(9009)) {
+        return 1;
+    }
+
+    qDebug() << "TCP server is running. Press Ctrl+C to exit...";
+
+    return app.exec();
+}
\ No newline at end of file
diff --git a/Test/CMakeLists.txt b/Test/CMakeLists.txt
index 9b3ce8e..375a863 100644
--- a/Test/CMakeLists.txt
+++ b/Test/CMakeLists.txt
@@ -4,5 +4,5 @@ project(frelayTest LANGUAGES CXX)
 set(CMAKE_CXX_STANDARD 11)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
-add_executable(frelayTest protocolTest.cpp)
+add_executable(frelayTest protocolTest.cpp infoTest.h infoTest.cpp)
 target_link_libraries(frelayTest PRIVATE Protocol)
\ No newline at end of file
diff --git a/Test/infoTest.cpp b/Test/infoTest.cpp
new file mode 100644
index 0000000..b646938
--- /dev/null
+++ b/Test/infoTest.cpp
@@ -0,0 +1,83 @@
+#include "infoTest.h"
+
+#include <QDebug>
+#include <QElapsedTimer>
+
+int infoTest1()
+{
+    InfoClient ic;
+    ic.id = "1234567890";
+    ic.name = "Test";
+
+    InfoClientVec vec;
+    vec.vec.append(ic);
+
+    QByteArray qa;
+    QBuffer buf(&qa);
+    buf.open(QIODevice::ReadWrite);
+
+    QDataStream qs(&buf);
+    vec.serialize(qs);
+    buf.close();
+
+    qDebug() << "Serialized data size:" << qa.size();
+    qDebug() << "Serialized data:" << qa.toHex();
+
+    QBuffer buf2(&qa);
+    buf2.open(QIODevice::ReadWrite);
+    QDataStream qs2(&buf2);
+    InfoClientVec vec2;
+    vec2.deserialize(qs2);
+    buf2.close();
+
+    return 0;
+}
+
+int infoTest2()
+{
+    InfoClient ic;
+    ic.id = "1234567890";
+    ic.name = "Test";
+
+    InfoClientVec vec;
+    vec.vec.append(ic);
+
+    QByteArray qa;
+    QDataStream qs(&qa, QIODevice::ReadWrite);
+    vec.serialize(qs);
+
+    qDebug() << "Serialized data size:" << qa.size();
+    qDebug() << "Serialized data:" << qa.toHex();
+
+    qs.device()->seek(0);
+    InfoClientVec vec2;
+    vec2.deserialize(qs);
+
+    return 0;
+}
+
+void performanceTest()
+{
+    QByteArray data;
+    QElapsedTimer timer;
+
+    timer.start();
+    QDataStream stream(&data, QIODevice::ReadWrite);
+    for (int i = 0; i < 10000; ++i) {
+        stream << i;
+        stream.device()->seek(0);
+        int val;
+        stream >> val;
+    }
+    qDebug() << "Reuse stream:" << timer.elapsed() << "ms";
+
+    timer.start();
+    for (int i = 0; i < 10000; ++i) {
+        QDataStream out(&data, QIODevice::WriteOnly);
+        out << i;
+        QDataStream in(&data, QIODevice::ReadOnly);
+        int val;
+        in >> val;
+    }
+    qDebug() << "New streams:" << timer.elapsed() << "ms";
+}
\ No newline at end of file
diff --git a/Test/infoTest.h b/Test/infoTest.h
new file mode 100644
index 0000000..dac3ad4
--- /dev/null
+++ b/Test/infoTest.h
@@ -0,0 +1,10 @@
+#ifndef INFO_TEST_H_
+#define INFO_TEST_H_
+
+#include <InfoClient.h>
+
+int infoTest1();
+int infoTest2();
+void performanceTest();
+
+#endif
\ No newline at end of file
diff --git a/Test/protocolTest.cpp b/Test/protocolTest.cpp
index 4d6c740..265cd2c 100644
--- a/Test/protocolTest.cpp
+++ b/Test/protocolTest.cpp
@@ -1,7 +1,8 @@
 #include <Protocol.h>
 #include <QDebug>
+#include "infoTest.h"
 
-int main()
+int test1()
 {
     auto frame = QSharedPointer<FrameBuffer>::create();
     frame->type = FBT_CLI_BIN_FILEDATA;
@@ -14,6 +15,11 @@ int main()
     qDebug() << "Packed data hex:" << packet.toHex();
 
     auto ret = Protocol::ParseBuffer(packet);
+    return 0;
+}
 
+int main()
+{
+    performanceTest();
     return 0;
 }
\ No newline at end of file