Listen for Multicast across multiple ports

This is my first Multicast project and I cannot find a solution -
My environment is an Arduino Uno and Ethernet Shield 2 (WIZ 5500), using the Ethernet3 library.

I need to listen for the presence of UDP Multicast packets being broadcast on IP address and ports 50001 through 50012. I need to differentiate between streams present across the port range, to take action on each unique port when active. For example: Picture a row of 12 LEDs, where each LED represents a port (LED 1 for port 50001, LED 2 for port 50002, etc.). I need to light each of the LEDs while Multicast packets are present on the associated port.

I have successfully detected Multicast traffic on a single port - but I am not sure how to go about listening on multiple ports at once.

Below is the sketch that works great for detecting traffic on a single port -
Of course any help is greatly appreciated!

#include <SPI.h>

#include <Ethernet3.h>

#include <EthernetUdp3.h>

byte mac = { 0xA8, 0x61, 0x0A, 0xAE, 0x6A, 0x51 }; // MAC address of this Ethernet Shield.

EthernetUDP Udp;
IPAddress ip(192, 168, 100, 19); // static IP address that Arduino uses to connect to LAN.

IPAddress multicastip(224, 0, 2, 60); // the Multicast IP to listen on.

unsigned int multicastport = 50002; // the Multicast Port to listen on.

char packetBuffer[UDP_TX_PACKET_MAX_SIZE]; // buffer to hold incoming packet.

void setup() {

Ethernet.begin(mac, ip);

Udp.beginMulticast(multicastip, multicastport);


Serial.print ("Starting to Listen for UDP Multicast Traffic on IP: ");

Serial.print (multicastip);

Serial.print (" Port: ");

Serial.print (multicastport);


void loop() {

// if there’s data available, read a packet

int packetSize = Udp.parsePacket();

if (packetSize)


Serial.print("Received packet of size ");






I guess you've chosen the wrong hardware for your project. The WizNet chip can listen on only 4 ports at the same time.

My suggestion: change to a Linux based board (p.e. Raspberry Pi), the network support is much more flexible there.

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