UDP and TCP difference

TCP and UDP impelement demux and 复用

transfer layer <===> socket <===> process

TCP socket <===> 4 element(source port,destion port,source ip,destion ip),so it is connective, need accept
UDP socket <===> 2 element(destion port,destion ip),so it is non-connective, needed accept
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高级tcp/ip编程在线阅读

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