This function must be called after UDP.parsePacket().

    //print out the remote connection's IP address
    Serial.print(remote);

    Serial.print(" on port : ");
    //print out the remote connection's port
    Serial.println(Udp.remotePort());
  }

(:sourceend:)

Gets the IP address of the remote connection.

This function can only be successfully called after UDP.parsePacket().

  int packetSize = Udp.parsePacket();
  if(packetSize)
  {
    Serial.print("Received packet of size ");
    Serial.println(packetSize);
    Serial.print("From IP : ");

    IPAddress remote = Udp.remoteIP();

Serial.print(remote); Serial.print(" on port : ") //print out the remote connection's IP address

  Serial.println(Udp.remoteIP());

}

(:source lang=arduino:)

//print out the remote connection's IP address

  Serial.println(Udp.remoteIP());

Ethernet : UDP.remoteIP()

Description

Gets the IP address of the remote connection

Syntax

UDP.remoteIP();

Parameters

None

Returns

4 bytes : the IP address of the remote connection

Example

(:source:)
#include <SPI.h>        
#include <Ethernet.h>
#include <EthernetUdp.h>

// Enter a MAC address and IP address for your controller below.
// The IP address will be dependent on your local network:
byte mac[] = {  
  0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
IPAddress ip(192, 168, 1, 177);

unsigned int localPort = 8888;      // local port to listen on

// An EthernetUDP instance to let us send and receive packets over UDP
EthernetUDP Udp;

void setup() {
  // start the Ethernet and UDP:
  Ethernet.begin(mac,ip);
  Udp.begin(localPort);

}

void loop() {

  Udp.beginPacket(Udp.remoteIP(), Udp.remotePort());
    Udp.write("hello");
    Udp.endPacket();

}(:sourceend:)