Multi client TCP/IP communication

Hello I have been working on this TCP communication. I have been able to implement, the server and client communication. However, I have multiple clients (4). How do I make my server listen for new connection after receiving the first connection. Below are my codes. When I run my code, the first client connects, however the second clients does not connect.

SERVER CODE

clear;
clc;

% Create a TCP/IP server
serverAddress = '0.0.0.0';
serverPort = 5000;
serverSocket = tcpip(serverAddress, serverPort, 'NetworkRole', 'server');

% Open server socket
fopen(serverSocket);
disp('Server: Listening for client connections...');

try
    % Accept four client connections
    for i = 1:4
        disp(['Server: Waiting for client ', num2str(i), ' to connect...']);
        clientSocket = acceptConnection(serverSocket);
        disp(['Server: Client ', num2str(i), ' connected.']);

        % Receive data from client
        dataBytes = fread(clientSocket, 192, 'uint8');
        disp(['Server: Received data from client ', num2str(i)]);

        % Convert byte data back to a numeric array
        receivedData = zeros(24, 1); % Initialize the array to hold the received data
        for j = 1:24
            % Extract the 8 bytes corresponding to one double-precision number
            byteBlock = dataBytes((j-1)*8 + (1:8));
            % Convert the byte block to a double-precision number
            receivedData(j) = typecast(uint8(byteBlock), 'double');
        end

        % Process the received data as needed
        disp(['Server: Received data array: ', mat2str(receivedData)])

        response = 4*4;
        dataBytes_send = typecast(response, 'uint8')
        % Send response back to client
    fwrite(clientSocket, dataBytes_send);
    disp(['Server: Response sent to client ', num2str(i)]);

        % Close connection with the client
        fclose(clientSocket);
        disp(['Server: Connection with client ', num2str(i), ' closed.']);
    end

    % Close server
    fclose(serverSocket);
    disp('Server: Disconnected.');
catch exception
    % Close server and display error message
    fclose(serverSocket);
    disp(['Server: Error occurred - ', exception.message]);
end

function clientSocket = acceptConnection(serverSocket)
timeout = 20; % seconds
tic;
while serverSocket.BytesAvailable == 0
    if toc > timeout
        error('Server: Connection timeout.');
    end
end
clientSocket = serverSocket;
end

Client 1

% Create a TCP/IP client for sending solar power data
clientSolar = tcpclient('127.0.0.1', 5000);

try
    % Connect to the server
    fopen(clientSolar);
    disp('Solar Client: Connected to server.');

    % Convert data to bytes
    solar_power_bytes = typecast(solar_power(:), 'uint8');
    
    % Send solar power data to the server
    fwrite(clientSolar, solar_power_bytes);
    disp('Solar Client: Solar power data sent to server.');
  
    % Receive response from server
    dataBytes_R = read(clientSolar, 8, 'uint8');
    receivedData = typecast(dataBytes_R, 'double');

    % Display received data
    disp(['Received response from server for solar: ', num2str(receivedData)])

    % Close connection
    fclose(clientSolar);
    disp('Solar Client: Disconnected from server.');
catch exception
    % Close connection and display error message
    fclose(clientSolar);
    disp(['Solar Client: Error occurred - ', exception.message]);
end

Client 2

 % Create a TCP/IP client for sending wind power data
clientWind = tcpclient('127.0.0.1', 5000);

try
    % Connect to the server
    fopen(clientWind);
    disp('Wind Client: Connected to server.');

      % Convert data to bytes
    Wind_power_bytes = typecast(solar_power(:), 'uint8');
    
    % Send solar power data to the server
    fwrite(clientSolar, Wind_power_bytes);
    disp('Wind Client: Wind power data sent to server.');
       

   % Receive response from server
    dataBytes_R = read(clientWInd, 8, 'uint8');
    receivedData = typecast(dataBytes_R, 'double');

    % Display received data
    disp(['Received response from server for solar: ', num2str(receivedData)])

    % Close connection
    fclose(clientWind);
    disp('Wind Client: Disconnected from server.');
catch exception
    % Close connection and display error message
    fclose(clientWind);
    disp(['Wind Client: Error occurred - ', exception.message]);
end

Answer 1

[Hassaan]

@chizom wornu Some of the recommendations. See also the reference link.

MATLAB's Limitations: Unfortunately, MATLAB's built-in tcpip object does not natively support acting as a server that can accept multiple connections by itself.

Alternative MATLAB Approach: Consider using MATLAB's ability to interface with Java for more advanced networking capabilities. MATLAB can directly use Java classes, allowing you to implement a multi-client TCP server using Java's networking libraries. This requires knowledge of Java but can be more flexible and powerful than relying on MATLAB's built-in functions alone.

MATLAB External Interfaces: If your application must remain within MATLAB for other reasons (e.g., specialized mathematical or signal processing workflows), you can develop the TCP server in another language that is better suited for network programming and then interface with MATLAB using a mechanism like a MATLAB Engine API for Python, Java, or calling compiled C/C++ libraries from MATLAB.

Reference:

How to address server and multiple clients communicate using tcpip function? - MATLAB Answers - MATLAB Central (mathworks.com)

how to establish a connection between a server and two clients in matlab via tcp / ip by using an interface for the server an... - MATLAB Answers - MATLAB Central (mathworks.com)

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[chizom wornu]

I just sent all the data using one client. Am not good with Java