BroadcastServer | Broadcasts crypto-currency market data via Socket.io | Runtime Evironment library

Intro

There are a number of tutorials on creating a multicast publisher and receiver.

I used the one found here with a few modifications.

A few others:

• here
• here
• here

note that these tutorials are all quite similar.

Details:

The server runs on port 7777 and sends datagrams to 224.0.0.0 (I tested a couple of other ip's in the multicast range: 224.0.0.0 to 239.255.255.255, but these didn't work)

Client then joins the multicast group 224.0.0.0 and waits for a packet response (run as a thread)

extra: I send a message like: 123.23.13.12[host-name]:1234 as the datagram data.

Problem:

Multicast packets from server (on localhost) not reaching client (on localhost).

Clients include a java console application (code found below) and Android application on Android Emulator. Both clients do not receive multicast packets.

I know that the multicast packets are being sent as this is shown in Wireshark

Below you will find a basic example of that which I have.

TL;DR: Server sends multicast packets (confirmed via Wireshark) but client doesn't receive them.

Suggestions are very welcome!

UPDATE

Based on Just another Java programmer's comment, I check my firewall. Lo and behold, my firewall was dropping on the input and forward chains. I set this to acceptall incoming (temporarily)

Based on Ron Maupin's comments.

• I have changed the message sent to exclude the hostname, thus the message sent is 123.12.13.23:1234
• I have changed the multicast send address to 239.254.0.0 which is within the specified range (see Ron's comment)
• the multicast port is set to 7777
• the outgoing interface is set with s.setInterface(InetAddress.getLocalHost()) in the broadcastServer() try catch block

With these changes applied, the client(s) still do not receive any packets.

Code:

Server Side (Console App):