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POHow to verify data integrity between client-server connection?
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copied!<p>I recently developed an online multiplayer game and it's working fine. There's a central server handling TCP connections with clients, and they both receive and send data.<br> Is there a way to verify that the data sent hasn't been modified before the receiver reads it?<br> Does a TCP connection handle it in some way? If not what is the best way (not asking for code) to implement it?<br> By now I came up with those ideas:</p> <ul> <li>Modify the data sent adding some sort of verify-value, such the packet length.</li> <li>When a packet is received, ask the server to send it again and verify if they are equal.</li> </ul> <p>I searched for a common used solution but couldn't find much.<br> Encryption should be my last option.</p> <p><strong>Edit</strong><br> For a simple way to achieve this:</p> <ol> <li>MD5<br> <ul> <li><a href="http://en.wikipedia.org/wiki/MD5" rel="nofollow noreferrer">Wikipedia</a><br></li> <li><a href="https://stackoverflow.com/questions/415953/generate-md5-hash-in-java">Example</a></li> </ul></li> <li>SHA1<br> <ul> <li><a href="http://en.wikipedia.org/wiki/SHA-1" rel="nofollow noreferrer">Wikipedia</a><br></li> <li><a href="http://anyexample.com/programming/java/java_simple_class_to_compute_sha_1_hash.xml" rel="nofollow noreferrer">Example</a></li> </ul></li> <li>SSL<br> <ul> <li><a href="http://en.wikipedia.org/wiki/Transport_Layer_Security" rel="nofollow noreferrer">Wikipedia</a><br></li> <li><a href="http://stilius.net/java/java_ssl.php" rel="nofollow noreferrer">Example</a></li> </ul></li> </ol>

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