Why does UDP have a length field in the header and TCP does not?

Posted by IP Help on Stack Overflow See other posts from Stack Overflow or by IP Help
Published on 2008-11-11T17:42:43Z Indexed on 2010/05/02 20:28 UTC
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Why does UDP have a length field in the header and TCP does not?

I am guessing that the length of the segment in TCP is inferred from the IP header but one should be able to do the same for a UDP datagram

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