1 Include

UDP are include in the JAVA languages classes :

import java.net.*;

2 ICMP client

ICMP ECHO REQUESTs is used if the privilege can be obtained, otherwise it will try to establish a TCP connection on port 7 (Echo) of the destination host.

String host;
boolean status;
status = InetAddress.getByName(host).isReachable(timeOut);

comments: the GEDEX wait for an ICMP ECHO REQUEST in order to set the internals registers @2 (Destination MAC Address (32 LSB)), @3 (Destination MAC Address (16 MSB)) and @4 (Destination IP Address).

3 UDP client

String          host;
int             port;
byte[]          buffer = new byte[1024];
InetAddress     address = InetAddress.getByName(host);
DatagramSocket  socket = new DatagramSocket();
DatagramPacket  packet = new DatagramPacket(buffer, buffer.length, address, port);

socket.send(packet);
socket.close();

4 UDP server

String          host;
int             port;
byte[]          buffer = new byte[1024];

DatagramSocket serverSocket = new DatagramSocket(port);

while(1) {
   DatagramPacket serverPacket = new DatagramPacket(buffer, buffer.length);
   serverSocket.receive(serverPacket);
}

serverSocket.close();

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2016-02-15

Contents

1 Include

2 ICMP client

3 UDP client

4 UDP server