UDP Multicast Dgram size question RRS feed

  • Question

  • Hi to all,

    I am trying to send a series of bitmaps via a UDP Multicast socket using Dgram. I have read that this is limited in byte size and therefor am having issues.

    My question is:

    do i have to break the bitmap into smaller fragments to send?


    is there a better way?

    Does anyone have an idea of how VLC and the like do it?

    I really want to know if i'm heading in the right direction or should change direction.

    new to .net and c#
    Monday, May 11, 2009 9:10 AM


  • Relying on IP Fragmentation will not be good.  Say one fragment is dropped by the network, then the sender will have to send the whole bitmap again.  With a good reliable UDP protocol the sender machine should be able to automatically send only any dropped packets.

    There seem to be a few libraries which support reliable UDP see e.g. http://stackoverflow.com/questions/107668/what-do-you-use-when-you-need-reliable-udp  and http://stackoverflow.com/questions/31572/broadcast-like-udp-with-the-reliability-of-tcp
    http://www.alanjmcf.me.uk/ Please follow-up in the newsgroup. If I help, mark the question answered
    Wednesday, May 13, 2009 9:52 AM