Broadcasting/multicasting UDP

Is it possible to broadcast UDP packets directly from the host machine's IP address on a selected port so that anyone listening on that IP address/port can receive them? If not, how should a server go about finding an appropriate IP address/port within the 224.0.0.0 - 239.255.255.255 range to send packets on?

Dear Josh,
You send the UDP paket to a multicast (class D) IP address/port and the rest is the duty of the multicasting server.
The mechnism of multicasting and how could Java programmer make use of it is some thing missed in the documents availabe. I've searched for that but all I got is an RMS "Reliable Multicast Service" Libraries like:
JRMS at www.experimentalstuff.com
JGroups at www.JGroups.org
But these are libraries and focusing on the reliable multicast. If we need to multicast an audio stream we need only basic multicast using "MulticastSoket" from java.net package.
But again the system is no only a set of API's. The question is HOW to build a multicasting audio service using java and whta do we need with java??
the answer could be of great help
Ahmad Khalafallah
[email protected]

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  • My Network of Macs keep broadcasting to udp port 8612 every few seconds

    This problem was answered nicely by "Hunter3740" and Apple archieved it....It is still valid/needed for Mountain Lion!
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    Disclaimer
    The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.
    Liability Disclaimer
    In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.
    Posting
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  • Broadcasting, multicasting etc. - some help please

    Hi guys. I am writing this code for a uni project where i have to send stuff from clients to server etc but there is one problem. i have to have a broadcast function that will broadcast a message to everyone. now i generally use tcp in the program since i want reliable comms but just for this i dont care using udp and therefore multicasting. But how can i combine them together? i mean do i need a separate port for multicasting? also, i read this article: http://www.cdt.luth.se/~peppar/java/multicast_example/ and i cant understand something. Let suppose that i use a similar approach as the one the author of thid article used and that the clients can only receive stuff. why should the clients join the multicast group? i thought that only the sender needs to know the group. isnt that the case?

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