Node.js socket.setMulticastTTL() Method
The socket.setMulticastTTL() is an inbuilt application programming interface of class Socket within dgram module which is used to set or clear the IP_MULTICAST_TTL socket option which helps to specify how many number of IP hops that a packet is allowed to travel through the specified multicast traffic.
Syntax:
const socket.setMulticastTTL( ttl )
Parameters: This method takes integer value representing the number of IP hops that a packet is allowed to travel through the specified multicast traffic.
Return Value: This method does not return any value.
Example 1: Filename: index.js
// Node.js program to demonstrate the// server.setMulticastTTL() API // Importing dgram modulevar dgram = require('dgram'); // Creating and initializing client // and server socketvar client = dgram.createSocket("udp4");var server = dgram.createSocket("udp4");let broadcast_address = 12345; // Handling the message eventserver.on("message", function (msg) { // Displaying the client message process.stdout.write("UDP String: " + msg + "\n"); // Exiting process process.exit();}).bind(broadcast_address, () => { // Enable the IP_MULTICAST_TTL socket option // and specifiing the number of IP hopes // by using the setMulticastTTL() method server.setMulticastTTL(144);}); // Client sending message to serverclient.send("Hello", 0, 7, broadcast_address, "localhost"); |
Output:
UDP String: Hello
Example 2: Filename: index.js
// Node.js program to demonstrate the// server.setMulticastTTL() API // Importing dgram modulevar dgram = require('dgram'); // Creating and initializing client// and server socketvar client = dgram.createSocket("udp4");var server = dgram.createSocket("udp4"); // Handling the message eventserver.on("message", function (msg) { // Displaying the client message process.stdout.write("UDP String: " + msg + "\n"); // Exiting process process.exit(); }); // Handling the listening eventserver.on('listening', () => { const address = server.address(); console.log(`server listening ${address.address}:${address.port}`);}); // Binding server with port addressserver.bind(1234, () => { // Enable the IP_MULTICAST_TTL socket option // and specifiing the number of IP hopes // by using the setMulticastTTL() method server.setMulticastTTL(255);}); // Client sending message to serverclient.send("Hello", 0, 7, 1234, "localhost"); |
Run the index.js file using the following command:
node index.js
Output:
server listening 0.0.0.0:1234 UDP String: Hello
Reference: https://nodejs.org/dist/latest-v12.x/docs/api/dgram.html#dgram_socket_setmulticastttl_ttl
