{"id":776,"date":"2014-01-28T17:06:45","date_gmt":"2014-01-28T09:06:45","guid":{"rendered":"http:\/\/coderbee.net\/?p=776"},"modified":"2014-01-28T17:20:38","modified_gmt":"2014-01-28T09:20:38","slug":"tcpip-%e5%8d%8f%e8%ae%ae%e8%af%a6%e8%a7%a3-%e7%ac%ac19%e3%80%8120%e7%ab%a0-tcp%e7%9a%84%e6%95%b0%e6%8d%ae%e6%b5%81","status":"publish","type":"post","link":"https:\/\/coderbee.net\/index.php\/basis\/20140128\/776","title":{"rendered":"TCP\/IP \u534f\u8bae\u8be6\u89e3 \u7b2c19\u300120\u7ae0 TCP\u7684\u6570\u636e\u6d41"},"content":{"rendered":"<h1>\u7b2c19\u7ae0 \u4ea4\u4e92\u6570\u636e\u6d41<\/h1>\n<p>\u4ea4\u4e92\u6570\u636e\u603b\u662f\u4ee5\u5c0f\u4e8e\u6700\u5927\u62a5\u6587\u6bb5\u957f\u5ea6\uff08MSS\uff0cMaximum Segment 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\/>\n<img decoding=\"async\" src=\"\/\/coderbee.net\/wp-content\/uploads\/2014\/01\/TCP-slide-window.png\" alt=\"TCP\u7a97\u53e3\u6ed1\u52a8\" \/><\/p>\n<p>\u63a5\u6536\u65b9\u901a\u544a\u7684\u7a97\u53e3\u79f0\u4e3a\u63d0\u51fa\u7a97\u53e3\uff08offered window\uff09\uff0c\u8986\u76d6\u4e86\u4ece\u7b2c4\u5b57\u8282\u5230\u7b2c9\u5b57\u8282\u7684\u533a\u57df\uff0c\u8868\u660e\u63a5\u6536\u65b9\u5df2\u7ecf\u786e\u8ba4\u4e86\u5305\u62ec\u7b2c3\u5b57\u8282\u5728\u5185\u7684\u6570\u636e\uff0c\u4e14\u901a\u544a\u7a97\u53e3\u5927\u5c0f\u4e3a6\u3002\u7a97\u53e3\u5927\u5c0f\u662f\u4e0e\u786e\u8ba4\u5e8f\u53f7\u76f8\u5bf9\u5e94\u7684\u3002\u53d1\u9001\u65b9\u8ba1\u7b97\u5b83\u7684\u53ef\u7528\u7a97\u53e3\uff0c\u8be5\u7a97\u53e3\u8868\u660e\u591a\u5c11\u6570\u636e\u53ef\u4ee5\u7acb\u5373\u88ab\u53d1\u9001\u3002<\/p>\n<p>\u7a97\u53e3\u5de6\u53f3\u8fb9\u6cbf\u7684\u8fd0\u52a8\uff1a<br \/>\n<img decoding=\"async\" src=\"\/\/coderbee.net\/wp-content\/uploads\/2014\/01\/TCP-slide-type-300x70.png\" alt=\"TCP-slide-type\" \/><\/p>\n<ul>\n<li>\u7a97\u53e3\u5de6\u8fb9\u6cbf\u5411\u53f3\u9760\u8fd1\u4e3a\u7a97\u53e3\u5408\u62e2\uff0c\u8fd9\u79cd\u73b0\u8c61\u53d1\u751f\u5728\u6570\u636e\u88ab\u53d1\u9001\u548c\u786e\u8ba4\u65f6\u3002<\/li>\n<li>\u7a97\u53e3\u53f3\u8fb9\u6cbf\u5411\u53f3\u79fb\u52a8\u65f6\u5c06\u5141\u8bb8\u53d1\u9001\u66f4\u591a\u7684\u6570\u636e\uff0c\u79f0\u4e3a\u7a97\u53e3\u5f20\u5f00\u3002\u8fd9\u79cd\u73b0\u8c61\u53d1\u751f\u5728\u53e6\u4e00\u7aef\u7684\u63a5\u6536\u8fdb\u7a0b\u8bfb\u53d6\u5df2\u7ecf\u786e\u8ba4\u7684\u6570\u636e\u5e76\u91ca\u653e\u4e86TCP\u7684\u63a5\u6536\u7f13\u5b58\u65f6\u3002<\/li>\n<li>\u5f53\u53f3\u8fb9\u6cbf\u5411\u5de6\u79fb\u52a8\u65f6\uff0c\u79f0\u4e3a\u7a97\u53e3\u6536\u7f29\u3002<\/li>\n<\/ul>\n<p>\u53d1\u9001\u65b9\u4e0d\u5fc5\u53d1\u9001\u4e00\u4e2a\u5168\u7a97\u53e3\u5927\u5c0f\u7684\u6570\u636e\u62a5\uff1b<br \/>\n\u6765\u81ea\u63a5\u6536\u65b9\u7684\u62a5\u6587\u6bb5\u786e\u8ba4\u6570\u636e\u5e76\u628a\u7a97\u53e3\u5411\u53f3\u6ed1\u52a8\uff0c\u8fd9\u662f\u56e0\u4e3a\u7a97\u53e3\u5927\u5c0f\u662f\u76f8\u5bf9\u4e8e\u786e\u8ba4\u5e8f\u53f7\u7684\u3002<\/p>\n<p>\u7531\u63a5\u6536\u65b9\u63d0\u4f9b\u7684\u7a97\u53e3\u5927\u5c0f\u901a\u5e38\u53ef\u4ee5\u7531\u63a5\u6536\u8fdb\u7a0b\u63a7\u5236\uff0c\u5c06\u5f71\u54cdTCP\u7684\u6027\u80fd\u3002<\/p>\n<h3>PUSH \u6807\u5fd7<\/h3>\n<p>PUSH \u6807\u5fd7\u901a\u77e5\u63a5\u6536\u65b9\u5c06\u6240\u6536\u5230\u7684\u6570\u636e\u5168\u90e8\u63d0\u4ea4\u7ed9\u63a5\u6536\u8fdb\u7a0b\u3002\u8fd9\u91cc\u7684\u6570\u636e\u5305\u62ec\u4e0ePUSH\u4e00\u8d77\u4f20\u9001\u7684\u6570\u636e\u4ee5\u53ca\u63a5\u6536\u65b9TCP\u5df2\u7ecf\u4e3a\u63a5\u6536\u8fdb\u7a0b\u6536\u5230\u7684\u5176\u4ed6\u6570\u636e\u3002<\/p>\n<h3>\u6162\u542f\u52a8<\/h3>\n<p>\u6162\u542f\u52a8\uff08slow start\uff09\u7b97\u6cd5\u901a\u8fc7\u89c2\u5bdf\u5230\u65b0\u5206\u7ec4\u8fdb\u5165\u7f51\u7edc\u7684\u901f\u7387\u5e94\u8be5\u4e0e\u53e6\u4e00\u7aef\u8fd4\u56de\u786e\u8ba4\u7684\u901f\u7387\u76f8\u540c\u800c\u8fdb\u884c\u5de5\u4f5c\u3002<\/p>\n<p>\u6162\u542f\u52a8\u4e3a\u53d1\u9001\u65b9\u7684TCP\u589e\u52a0\u4e86\u53e6\u4e00\u4e2a\u7a97\u53e3\uff1a\u62e5\u585e\u7a97\u53e3\uff08congestion window\uff09\uff0c\u8bb0\u4e3acwnd\u3002<\/p>\n<p>\u5f53\u4e0e\u53e6\u4e00\u4e2a\u7f51\u7edc\u7684\u4e3b\u673a\u5efa\u7acbTCP\u8fde\u63a5\u65f6\uff0c\u62e5\u585e\u7a97\u53e3\u88ab\u521d\u59cb\u5316\u4e3a1\u4e2a\u62a5\u6587\u6bb5\uff08\u5373\u53e6\u4e00\u7aef\u901a\u544a\u7684\u62a5\u6587\u6bb5\u5927\u5c0f\uff09\u3002\u6bcf\u6536\u5230\u4e00\u4e2aACK\uff0c\u62e5\u585e\u7a97\u53e3\u5c31\u589e\u52a0\u4e00\u4e2a\u62a5\u6587\u6bb5\uff08cwnd\u4ee5\u5b57\u8282\u4e3a\u5355\u4f4d\uff0c\u4f46\u662f\u6162\u542f\u52a8\u4ee5\u62a5\u6587\u6bb5\u5927\u5c0f\u4e3a\u5355\u4f4d\u8fdb\u884c\u589e\u52a0\uff09\u3002\u53d1\u9001\u65b9\u53d6\u62e5\u585e\u7a97\u53e3\u4e0e\u901a\u544a\u7a97\u53e3\u4e2d\u7684\u6700\u5c0f\u503c\u4f5c\u4e3a\u53d1\u9001\u4e0a\u9650\u3002<\/p>\n<p><strong>\u62e5\u585e\u7a97\u53e3\u662f\u53d1\u9001\u65b9\u4f7f\u7528\u7684\u6d41\u91cf\u63a7\u5236\uff0c\u800c\u901a\u544a\u7a97\u53e3\u5219\u662f\u63a5\u6536\u65b9\u4f7f\u7528\u7684\u6d41\u91cf\u63a7\u5236\u3002<\/strong><\/p>\n<p>\u53d1\u9001\u65b9\u5f00\u59cb\u65f6\u53d1\u9001\u4e00\u4e2a\u62a5\u6587\u6bb5\uff0c\u7136\u540e\u7b49\u5f85ACK\u3002\u5f53\u6536\u5230\u8be5ACK\u65f6\uff0c\u62e5\u585e\u7a97\u53e3\u4ece1\u589e\u52a0\u52302\uff0c\u65e2\u53ef\u4ee5\u53d1\u9001\u4e24\u4e2a\u62a5\u6587\u6bb5\u3002\u5f53\u6536\u5230\u8fd9\u4e24\u4e2a\u62a5\u6587\u6bb5\u7684ACK\u65f6\uff0c\u62e5\u585e\u7a97\u53e3\u5c31\u589e\u52a0\u4e3a4\u3002\u8fd9\u662f\u4e00\u79cd\u6307\u6570\u589e\u52a0\u7684\u5173\u7cfb\u3002<\/p>\n<hr\/>\n<p>\u6b22\u8fce\u5173\u6ce8\u6211\u7684\u5fae\u4fe1\u516c\u4f17\u53f7: <strong>coderbee\u7b14\u8bb0<\/strong>\uff0c\u53ef\u4ee5\u66f4\u53ca\u65f6\u56de\u590d\u4f60\u7684\u8ba8\u8bba\u3002<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" width=\"258\" height=\"258\" src=\"https:\/\/coderbee.net\/wp-content\/uploads\/2019\/01\/coderbee-note.jpg\" class=\"alignnone size-full wp-image-1707\"><\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u7b2c19\u7ae0 \u4ea4\u4e92\u6570\u636e\u6d41 \u4ea4\u4e92\u6570\u636e\u603b\u662f\u4ee5\u5c0f\u4e8e\u6700\u5927\u62a5\u6587\u6bb5\u957f\u5ea6\uff08MSS\uff0cMaximum  &hellip; <a href=\"https:\/\/coderbee.net\/index.php\/basis\/20140128\/776\">\u7ee7\u7eed\u9605\u8bfb <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[83],"tags":[153],"_links":{"self":[{"href":"https:\/\/coderbee.net\/index.php\/wp-json\/wp\/v2\/posts\/776"}],"collection":[{"href":"https:\/\/coderbee.net\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/coderbee.net\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/coderbee.net\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/coderbee.net\/index.php\/wp-json\/wp\/v2\/comments?post=776"}],"version-history":[{"count":3,"href":"https:\/\/coderbee.net\/index.php\/wp-json\/wp\/v2\/posts\/776\/revisions"}],"predecessor-version":[{"id":781,"href":"https:\/\/coderbee.net\/index.php\/wp-json\/wp\/v2\/posts\/776\/revisions\/781"}],"wp:attachment":[{"href":"https:\/\/coderbee.net\/index.php\/wp-json\/wp\/v2\/media?parent=776"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/coderbee.net\/index.php\/wp-json\/wp\/v2\/categories?post=776"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/coderbee.net\/index.php\/wp-json\/wp\/v2\/tags?post=776"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}