RDT Project Implement Checksum, Ack

I need to implement reliable data transfer using checksums, ACKs, sequence numbers and countdown timers and implement the following functions.

  public static int compute_checksum(String message) {}



  public static boolean isCorrupt(rdtPacket packet) {}



  public static boolean isACK(rdtPacket packet) {}



  public static boolean inOrder(rdtPacket packet, int seqno) {} // has_seq()

And add a countdown timer to the socket when waiting for ACKs.

Additionally, the packet format will be:

message checksum sequence number

Finally, ACKs will be sent using the message "ACK"

This is what I have so far:

import java.io.*;

import java.net.*;



class RDTClient {

  private static DatagramSocket clientSocket;

  private static InetAddress IPAddress;

  private static final int serverPort = 9876;



  public static void main(String args) throws Exception {

    try {

      String serverHostname = new String("127.0.0.1");



      if (args.length > 0) {

        serverHostname = args[0];

      }



      BufferedReader inFromUser = new BufferedReader(new InputStreamReader(System.in));



      clientSocket = new DatagramSocket();



      IPAddress = InetAddress.getByName(serverHostname);

      System.out.println("Attemping to connect to " + IPAddress + ") via UDP port " + serverPort);



      System.out.print("Enter Message: ");

      String message = inFromUser.readLine();



      rdt_send(message);



      // String response = rdt_rcv();

      // System.out.println("Received response: " + response);



      clientSocket.close();

    } catch (UnknownHostException ex) {

      System.err.println(ex);

    } catch (IOException ex) {

      System.err.println(ex);

    }

  }



  private static String make_pkt(String message) {

    System.out.println("[RDTClient:make_pkt] " + message);

    return message;

  }



  private static void rdt_send(String message) {

    System.out.println("[RDTClient:rdt_send] " + message);

    String packet = make_pkt(message);

    udt_send(packet);

  }



  private static void udt_send(String message) {

    // compute the message checksum and create the segment rdt_send and make_pkt

    try {

      byte sendData = new byte[1024];

      sendData = message.getBytes();

      DatagramPacket sendPacket =

      new DatagramPacket(sendData, sendData.length, IPAddress, serverPort);

      clientSocket.send(sendPacket);

      System.out.println("[RDTClient:udt_send] Message sent");

    } catch (IOException ioe) {

      System.out.println("Failed to send");

    }

  }



  private static String rdt_rcv() {

    try {

      byte receiveData = new byte[1024];

      DatagramPacket receivePacket = new DatagramPacket(receiveData, receiveData.length);

      clientSocket.setSoTimeout(10000);

      clientSocket.receive(receivePacket);

      String message = new String(receivePacket.getData());

      IPAddress = receivePacket.getAddress();

      int port = receivePacket.getPort();



      System.out.println("[RDTClient:rdt_rcv] Received packet from: " + IPAddress + ":" + port);

      return message;

    } catch (IOException ioe) {

      System.out.println("Failed to read from port");

    }

    return "";

  }

}

asked Nov 22 '18 at 1:20

Mannie

add a comment |

I need to implement reliable data transfer using checksums, ACKs, sequence numbers and countdown timers and implement the following functions.

  public static int compute_checksum(String message) {}



  public static boolean isCorrupt(rdtPacket packet) {}



  public static boolean isACK(rdtPacket packet) {}



  public static boolean inOrder(rdtPacket packet, int seqno) {} // has_seq()

And add a countdown timer to the socket when waiting for ACKs.

Additionally, the packet format will be:

message checksum sequence number

Finally, ACKs will be sent using the message "ACK"

This is what I have so far:

import java.io.*;

import java.net.*;



class RDTClient {

  private static DatagramSocket clientSocket;

  private static InetAddress IPAddress;

  private static final int serverPort = 9876;



  public static void main(String args) throws Exception {

    try {

      String serverHostname = new String("127.0.0.1");



      if (args.length > 0) {

        serverHostname = args[0];

      }



      BufferedReader inFromUser = new BufferedReader(new InputStreamReader(System.in));



      clientSocket = new DatagramSocket();



      IPAddress = InetAddress.getByName(serverHostname);

      System.out.println("Attemping to connect to " + IPAddress + ") via UDP port " + serverPort);



      System.out.print("Enter Message: ");

      String message = inFromUser.readLine();



      rdt_send(message);



      // String response = rdt_rcv();

      // System.out.println("Received response: " + response);



      clientSocket.close();

    } catch (UnknownHostException ex) {

      System.err.println(ex);

    } catch (IOException ex) {

      System.err.println(ex);

    }

  }



  private static String make_pkt(String message) {

    System.out.println("[RDTClient:make_pkt] " + message);

    return message;

  }



  private static void rdt_send(String message) {

    System.out.println("[RDTClient:rdt_send] " + message);

    String packet = make_pkt(message);

    udt_send(packet);

  }



  private static void udt_send(String message) {

    // compute the message checksum and create the segment rdt_send and make_pkt

    try {

      byte sendData = new byte[1024];

      sendData = message.getBytes();

      DatagramPacket sendPacket =

      new DatagramPacket(sendData, sendData.length, IPAddress, serverPort);

      clientSocket.send(sendPacket);

      System.out.println("[RDTClient:udt_send] Message sent");

    } catch (IOException ioe) {

      System.out.println("Failed to send");

    }

  }



  private static String rdt_rcv() {

    try {

      byte receiveData = new byte[1024];

      DatagramPacket receivePacket = new DatagramPacket(receiveData, receiveData.length);

      clientSocket.setSoTimeout(10000);

      clientSocket.receive(receivePacket);

      String message = new String(receivePacket.getData());

      IPAddress = receivePacket.getAddress();

      int port = receivePacket.getPort();



      System.out.println("[RDTClient:rdt_rcv] Received packet from: " + IPAddress + ":" + port);

      return message;

    } catch (IOException ioe) {

      System.out.println("Failed to read from port");

    }

    return "";

  }

}

asked Nov 22 '18 at 1:20

Mannie

add a comment |

I need to implement reliable data transfer using checksums, ACKs, sequence numbers and countdown timers and implement the following functions.

  public static int compute_checksum(String message) {}



  public static boolean isCorrupt(rdtPacket packet) {}



  public static boolean isACK(rdtPacket packet) {}



  public static boolean inOrder(rdtPacket packet, int seqno) {} // has_seq()

And add a countdown timer to the socket when waiting for ACKs.

Additionally, the packet format will be:

message checksum sequence number

Finally, ACKs will be sent using the message "ACK"

This is what I have so far:

import java.io.*;

import java.net.*;



class RDTClient {

  private static DatagramSocket clientSocket;

  private static InetAddress IPAddress;

  private static final int serverPort = 9876;



  public static void main(String args) throws Exception {

    try {

      String serverHostname = new String("127.0.0.1");



      if (args.length > 0) {

        serverHostname = args[0];

      }



      BufferedReader inFromUser = new BufferedReader(new InputStreamReader(System.in));



      clientSocket = new DatagramSocket();



      IPAddress = InetAddress.getByName(serverHostname);

      System.out.println("Attemping to connect to " + IPAddress + ") via UDP port " + serverPort);



      System.out.print("Enter Message: ");

      String message = inFromUser.readLine();



      rdt_send(message);



      // String response = rdt_rcv();

      // System.out.println("Received response: " + response);



      clientSocket.close();

    } catch (UnknownHostException ex) {

      System.err.println(ex);

    } catch (IOException ex) {

      System.err.println(ex);

    }

  }



  private static String make_pkt(String message) {

    System.out.println("[RDTClient:make_pkt] " + message);

    return message;

  }



  private static void rdt_send(String message) {

    System.out.println("[RDTClient:rdt_send] " + message);

    String packet = make_pkt(message);

    udt_send(packet);

  }



  private static void udt_send(String message) {

    // compute the message checksum and create the segment rdt_send and make_pkt

    try {

      byte sendData = new byte[1024];

      sendData = message.getBytes();

      DatagramPacket sendPacket =

      new DatagramPacket(sendData, sendData.length, IPAddress, serverPort);

      clientSocket.send(sendPacket);

      System.out.println("[RDTClient:udt_send] Message sent");

    } catch (IOException ioe) {

      System.out.println("Failed to send");

    }

  }



  private static String rdt_rcv() {

    try {

      byte receiveData = new byte[1024];

      DatagramPacket receivePacket = new DatagramPacket(receiveData, receiveData.length);

      clientSocket.setSoTimeout(10000);

      clientSocket.receive(receivePacket);

      String message = new String(receivePacket.getData());

      IPAddress = receivePacket.getAddress();

      int port = receivePacket.getPort();



      System.out.println("[RDTClient:rdt_rcv] Received packet from: " + IPAddress + ":" + port);

      return message;

    } catch (IOException ioe) {

      System.out.println("Failed to read from port");

    }

    return "";

  }

}

asked Nov 22 '18 at 1:20

Mannie

I need to implement reliable data transfer using checksums, ACKs, sequence numbers and countdown timers and implement the following functions.

  public static int compute_checksum(String message) {}



  public static boolean isCorrupt(rdtPacket packet) {}



  public static boolean isACK(rdtPacket packet) {}



  public static boolean inOrder(rdtPacket packet, int seqno) {} // has_seq()

And add a countdown timer to the socket when waiting for ACKs.

Additionally, the packet format will be:

message checksum sequence number

Finally, ACKs will be sent using the message "ACK"

This is what I have so far:

import java.io.*;

import java.net.*;



class RDTClient {

  private static DatagramSocket clientSocket;

  private static InetAddress IPAddress;

  private static final int serverPort = 9876;



  public static void main(String args) throws Exception {

    try {

      String serverHostname = new String("127.0.0.1");



      if (args.length > 0) {

        serverHostname = args[0];

      }



      BufferedReader inFromUser = new BufferedReader(new InputStreamReader(System.in));



      clientSocket = new DatagramSocket();



      IPAddress = InetAddress.getByName(serverHostname);

      System.out.println("Attemping to connect to " + IPAddress + ") via UDP port " + serverPort);



      System.out.print("Enter Message: ");

      String message = inFromUser.readLine();



      rdt_send(message);



      // String response = rdt_rcv();

      // System.out.println("Received response: " + response);



      clientSocket.close();

    } catch (UnknownHostException ex) {

      System.err.println(ex);

    } catch (IOException ex) {

      System.err.println(ex);

    }

  }



  private static String make_pkt(String message) {

    System.out.println("[RDTClient:make_pkt] " + message);

    return message;

  }



  private static void rdt_send(String message) {

    System.out.println("[RDTClient:rdt_send] " + message);

    String packet = make_pkt(message);

    udt_send(packet);

  }



  private static void udt_send(String message) {

    // compute the message checksum and create the segment rdt_send and make_pkt

    try {

      byte sendData = new byte[1024];

      sendData = message.getBytes();

      DatagramPacket sendPacket =

      new DatagramPacket(sendData, sendData.length, IPAddress, serverPort);

      clientSocket.send(sendPacket);

      System.out.println("[RDTClient:udt_send] Message sent");

    } catch (IOException ioe) {

      System.out.println("Failed to send");

    }

  }



  private static String rdt_rcv() {

    try {

      byte receiveData = new byte[1024];

      DatagramPacket receivePacket = new DatagramPacket(receiveData, receiveData.length);

      clientSocket.setSoTimeout(10000);

      clientSocket.receive(receivePacket);

      String message = new String(receivePacket.getData());

      IPAddress = receivePacket.getAddress();

      int port = receivePacket.getPort();



      System.out.println("[RDTClient:rdt_rcv] Received packet from: " + IPAddress + ":" + port);

      return message;

    } catch (IOException ioe) {

      System.out.println("Failed to read from port");

    }

    return "";

  }

}

java checksum transfer ack

asked Nov 22 '18 at 1:20

Mannie

asked Nov 22 '18 at 1:20

Mannie

asked Nov 22 '18 at 1:20

Mannie

asked Nov 22 '18 at 1:20

Mannie

asked Nov 22 '18 at 1:20

Mannie

add a comment |

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