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Thread: Java program to create CRC on sending and receiving UDP datagram

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    Default Java program to create CRC on sending and receiving UDP datagram

    Hi, How can I create CRC (Cyclic redundancy check - Wikipedia, the free encyclopedia) when i send and recive UDP datagram?


  2. #2

    Default Re: DatagramPacket CRC

    Koren I see you are working a lot with datagrams. I'm not an expert but I'll do my best.

    Did you read something at the sun site? Lesson: All About Datagrams (The Java™ Tutorials > Custom Networking)

    Also you can read something about UDP checksum here and here

    And I've just read this paragraph answering a question:

    "Do I have to perform the check sum checking myself, or does the JVM, my OS or anything else discard any UDP datagrams with an invalid check sum?
    Verifying UDP checksums is a task for the UDP protocol driver, which is implemented in your operating system's network stack. You do not have to - nor can you - verify the UDP checksums on an UDP socket.
    Remember the network model is a layered one. TCP and UDP are layer 4; they are the transport layer, which takes care of transporting the data you send in the socket (which is therefore layer 5 and above). What you receive on a socket is what the other side sent through its own socket - just the layer 5 and above data."

    I hope this'll help you

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    Default Re: DatagramPacket CRC

    Yes thanks a lot!!!

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    Default Re: DatagramPacket CRC

    Hey Koren3,

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