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src=\"https:\/\/lemon-guess.oss-cn-hangzhou.aliyuncs.com\/1845293-20191213234811404-903775722.png\" alt=\"\" \/><\/p>\n<p>\u4e3e\u4e2a\u6817\u5b50\uff1a\u628a\u5ba2\u6237\u7aef\u6bd4\u4f5c\u7537\u5b69\uff0c\u670d\u52a1\u5668\u6bd4\u4f5c\u5973\u5b69\u3002\u901a\u8fc7\u4ed6\u4eec\u7684\u5206\u624b\u6765\u8bf4\u660e\u201c\u56db\u6b21\u6325\u624b\u201d\u8fc7\u7a0b\u3002<\/p>\n<ul>\n<li>\n<p>&quot;\u7b2c\u4e00\u6b21\u6325\u624b&quot;\uff1a\u65e5\u4e45\u89c1\u4eba\u5fc3\uff0c\u7537\u5b69\u53d1\u73b0\u5973\u5b69\u53d8\u6210\u4e86\u81ea\u5df1\u8ba8\u538c\u7684\u6837\u5b50\uff0c\u5fcd\u65e0\u53ef\u5fcd\uff0c\u4e8e\u662f\u51b3\u5b9a\u5206\u624b\uff0c\u968f\u5373\u5199\u4e86\u4e00\u5c01\u4fe1\u544a\u8bc9\u5973\u5b69\u3002<\/p>\n<\/li>\n<li>\n<p>\u201c\u7b2c\u4e8c\u6b21\u6325\u624b\u201d\uff1a\u5973\u5b69\u6536\u5230\u4fe1\u4e4b\u540e\uff0c<strong>\u77e5\u9053\u4e86\u7537\u5b69\u8981\u548c\u81ea\u5df1\u5206\u624b<\/strong>\uff0c\u6012\u706b\u4e2d\u70e7\uff0c\u5fc3\u4e2d\u6697\u9a82\uff1a\u4f60\u7b97\u4ec0\u4e48\u4e1c\u897f\uff0c\u5f53\u521d\u4f60\u53ef\u4e0d\u662f\u8fd9\u4e2a\u6837\u5b50\u7684\uff01\u4e8e\u662f\u7acb\u9a6c\u7ed9\u7537\u5b69\u5199\u4e86\u4e00\u5c01\u56de\u4fe1\uff1a\u5206\u624b\u5c31\u5206\u624b\uff0c\u7ed9\u6211\u70b9\u65f6\u95f4\uff0c\u6211\u8981\u628a\u4f60\u7684\u4e1c\u897f\u6574\u7406\u597d\uff0c\u5168\u90e8\u8fd8\u7ed9\u4f60\uff01<\/p>\n<p>\u7537\u5b69\u6536\u5230\u5973\u5b69\u7684\u7b2c\u4e00\u5c01\u4fe1\u4e4b\u540e\uff0c<strong>\u660e\u767d\u4e86\u5973\u5b69\u77e5\u9053\u81ea\u5df1\u8981\u548c\u5979\u5206\u624b<\/strong>\u3002\u968f\u540e\u7b49\u5f85\u5973\u5b69\u628a\u81ea\u5df1\u7684\u4e1c\u897f\u6536\u62fe\u597d\u3002<\/p>\n<\/li>\n<li>\n<p>\u201c\u7b2c\u4e09\u6b21\u6325\u624b\u201d\uff1a\u8fc7\u4e86\u51e0\u5929\uff0c\u5973\u5b69\u628a\u7537\u5b69\u9001\u7684\u4e1c\u897f\u90fd\u6574\u7406\u597d\u4e86\uff0c\u4e8e\u662f\u518d\u6b21\u5199\u4fe1\u7ed9\u7537\u5b69\uff1a\u4f60\u7684\u4e1c\u897f\u6211\u6574\u7406\u597d\u4e86\uff0c\u5feb\u628a\u5b83\u4eec\u62ff\u8d70\uff0c\u4ece\u6b64\u4f60\u6211\u6069\u65ad\u4e49\u7edd\uff01<\/p>\n<\/li>\n<li>\n<p>\u201c\u7b2c\u56db\u6b21\u6325\u624b\u201d\uff1a\u7537\u5b69\u6536\u5230\u5973\u5b69\u7b2c\u4e8c\u5c01\u4fe1\u4e4b\u540e\uff0c<strong>\u77e5\u9053\u4e86\u5973\u5b69\u6536\u62fe\u597d\u4e1c\u897f\u4e86\uff0c\u53ef\u4ee5\u6b63\u5f0f\u5206\u624b\u4e86<\/strong>\uff0c\u4e8e\u662f\u518d\u6b21\u5199\u4fe1\u544a\u8bc9\u5973\u5b69\uff1a\u6211\u77e5\u9053\u4e86\uff0c\u8fd9\u5c31\u53bb\u62ff\u56de\u6765\uff01<\/p>\n<\/li>\n<\/ul>\n<p>\u8fd9\u91cc\u53cc\u65b9\u90fd\u6709\u5404\u81ea\u7684\u575a\u6301\u3002<\/p>\n<ul>\n<li>\u5973\u5b69\u81ea\u53d1\u51fa\u7b2c\u4e8c\u5c01\u4fe1\u5f00\u59cb\uff0c\u9650\u5b9a\u4e00\u5929\u5185\u6536\u4e0d\u5230\u7537\u5b69\u56de\u4fe1\uff0c\u5c31\u4f1a\u518d\u53d1\u4e00\u5c01\u4fe1\u50ac\u4fc3\u7537\u5b69\u6765\u53d6\u4e1c\u897f\uff01<\/li>\n<li>\u7537\u5b69\u81ea\u53d1\u51fa\u7b2c\u4e8c\u5c01\u4fe1\u5f00\u59cb\uff0c\u9650\u5b9a\u4e24\u5929\u5185\u6ca1\u6709\u518d\u6b21\u6536\u5230\u5973\u5b69\u7684\u4fe1\u5c31\u8ba4\u4e3a\uff0c\u5973\u5b69\u6536\u5230\u4e86\u81ea\u5df1\u7684\u7b2c\u4e8c\u5c01\u4fe1\uff1b\u82e5\u4e24\u5929\u5185\u518d\u6b21\u6536\u5230\u5973\u5b69\u7684\u6765\u4fe1\uff0c\u5c31\u8ba4\u4e3a\u81ea\u5df1\u7684\u7b2c\u4e8c\u5c01\u4fe1\u5973\u5b69\u6ca1\u6536\u5230\uff0c\u9700\u8981\u518d\u5199\u4e00\u5c01\u4fe1\uff0c\u518d\u7b49\u4e24\u5929.....<\/li>\n<\/ul>\n<p><strong>\u5018\u82e5\u53cc\u65b9\u4fe1\u90fd\u80fd\u6b63\u5e38\u6536\u5230\uff0c\u6700\u5c11\u53ea\u7528\u56db\u5c01\u4fe1\u5c31\u80fd\u5f7b\u5e95\u5206\u624b\uff01\u8fd9\u5c31\u662f\u201c\u56db\u6b21\u6325\u624b\u201d\u3002<\/strong><\/p>\n<h3>4.\u4e3a\u4ec0\u4e48\u201c\u63e1\u624b\u201d\u662f\u4e09\u6b21\uff0c\u201c\u6325\u624b\u201d\u5374\u8981\u56db\u6b21\uff1f<\/h3>\n<hr \/>\n<p>TCP\u5efa\u7acb\u8fde\u63a5\u65f6\u4e4b\u6240\u4ee5\u53ea\u9700\u8981&quot;\u4e09\u6b21\u63e1\u624b&quot;\uff0c\u662f\u56e0\u4e3a\u5728\u7b2c\u4e8c\u6b21&quot;\u63e1\u624b&quot;\u8fc7\u7a0b\u4e2d\uff0c\u670d\u52a1\u5668\u7aef\u53d1\u9001\u7ed9\u5ba2\u6237\u7aef\u7684TCP\u62a5\u6587\u662f\u4ee5<strong>SYN\u4e0eACK<\/strong>\u4f5c\u4e3a<strong>\u6807\u5fd7\u4f4d<\/strong>\u7684\u3002SYN\u662f\u8bf7\u6c42\u8fde\u63a5\u6807\u5fd7\uff0c\u8868\u793a\u670d\u52a1\u5668\u7aef\u540c\u610f\u5efa\u7acb\u8fde\u63a5\uff1bACK\u662f\u786e\u8ba4\u62a5\u6587\uff0c\u8868\u793a\u544a\u8bc9\u5ba2\u6237\u7aef\uff0c\u670d\u52a1\u5668\u7aef\u6536\u5230\u4e86\u5b83\u7684\u8bf7\u6c42\u62a5\u6587\u3002<\/p>\n<p><strong>\u5373SYN\u5efa\u7acb\u8fde\u63a5\u62a5\u6587\u4e0eACK\u786e\u8ba4\u63a5\u6536\u62a5\u6587\u662f\u5728\u540c\u4e00\u6b21&quot;\u63e1\u624b&quot;\u5f53\u4e2d\u4f20\u8f93\u7684<\/strong>\uff0c\u6240\u4ee5&quot;\u4e09\u6b21\u63e1\u624b&quot;\u4e0d\u591a\u4e5f\u4e0d\u5c11\uff0c\u6b63\u597d\u8ba9\u53cc\u65b9\u660e\u786e\u5f7c\u6b64\u4fe1\u606f\u4e92\u901a\u3002<\/p>\n<p>TCP\u91ca\u653e\u8fde\u63a5\u65f6\u4e4b\u6240\u4ee5\u9700\u8981\u201c\u56db\u6b21\u6325\u624b\u201d,\u662f\u56e0\u4e3a<strong>FIN\u91ca\u653e\u8fde\u63a5\u62a5\u6587\u4e0eACK\u786e\u8ba4\u63a5\u6536\u62a5\u6587\u662f\u5206\u522b\u7531\u7b2c\u4e8c\u6b21\u548c\u7b2c\u4e09\u6b21&quot;\u6325\u624b&quot;\u4f20\u8f93\u7684<\/strong>\u3002\u4e3a\u4f55\u5efa\u7acb\u8fde\u63a5\u65f6\u4e00\u8d77\u4f20\u8f93\uff0c\u91ca\u653e\u8fde\u63a5\u65f6\u5374\u8981\u5206\u5f00\u4f20\u8f93\uff1f<\/p>\n<ul>\n<li>\u5efa\u7acb\u8fde\u63a5\u65f6\uff0c\u88ab\u52a8\u65b9\u670d\u52a1\u5668\u7aef\u7ed3\u675fCLOSED\u9636\u6bb5\u8fdb\u5165\u201c\u63e1\u624b\u201d\u9636\u6bb5\u5e76\u4e0d\u9700\u8981\u4efb\u4f55\u51c6\u5907\uff0c\u53ef\u4ee5\u76f4\u63a5\u8fd4\u56deSYN\u548cACK\u62a5\u6587\uff0c\u5f00\u59cb\u5efa\u7acb\u8fde\u63a5\u3002<\/li>\n<li>\u91ca\u653e\u8fde\u63a5\u65f6\uff0c\u88ab\u52a8\u65b9\u670d\u52a1\u5668\uff0c\u7a81\u7136\u6536\u5230\u4e3b\u52a8\u65b9\u5ba2\u6237\u7aef\u91ca\u653e\u8fde\u63a5\u7684\u8bf7\u6c42\u65f6\u5e76\u4e0d\u80fd\u7acb\u5373\u91ca\u653e\u8fde\u63a5\uff0c\u56e0\u4e3a\u8fd8\u6709\u5fc5\u8981\u7684\u6570\u636e\u9700\u8981\u5904\u7406\uff0c\u6240\u4ee5\u670d\u52a1\u5668\u5148\u8fd4\u56deACK\u786e\u8ba4\u6536\u5230\u62a5\u6587\uff0c\u7ecf\u8fc7CLOSE-WAIT\u9636\u6bb5\u51c6\u5907\u597d\u91ca\u653e\u8fde\u63a5\u4e4b\u540e\uff0c\u624d\u80fd\u8fd4\u56deFIN\u91ca\u653e\u8fde\u63a5\u62a5\u6587\u3002<\/li>\n<\/ul>\n<p><strong>\u6240\u4ee5\u662f\u201c\u4e09\u6b21\u63e1\u624b\u201d\uff0c\u201c\u56db\u6b21\u6325\u624b\u201d\u3002<\/strong><\/p>\n<h3>5.\u4e3a\u4ec0\u4e48\u5ba2\u6237\u7aef\u5728TIME-WAIT\u9636\u6bb5\u8981\u7b492MSL?<\/h3>\n<hr \/>\n<p><strong>\u4e3a\u7684\u662f\u786e\u8ba4\u670d\u52a1\u5668\u7aef\u662f\u5426\u6536\u5230\u5ba2\u6237\u7aef\u53d1\u51fa\u7684ACK\u786e\u8ba4\u62a5\u6587<\/strong><\/p>\n<p>\u5f53\u5ba2\u6237\u7aef\u53d1\u51fa\u6700\u540e\u7684ACK\u786e\u8ba4\u62a5\u6587\u65f6\uff0c\u5e76\u4e0d\u80fd\u786e\u5b9a\u670d\u52a1\u5668\u7aef\u80fd\u591f\u6536\u5230\u8be5\u6bb5\u62a5\u6587\u3002\u6240\u4ee5\u5ba2\u6237\u7aef\u5728\u53d1\u9001\u5b8cACK\u786e\u8ba4\u62a5\u6587\u4e4b\u540e\uff0c\u4f1a\u8bbe\u7f6e\u4e00\u4e2a\u65f6\u957f\u4e3a2MSL\u7684\u8ba1\u65f6\u5668\u3002MSL\u6307\u7684\u662fMaximum Segment Lifetime\uff1a\u4e00\u6bb5TCP\u62a5\u6587\u5728\u4f20\u8f93\u8fc7\u7a0b\u4e2d\u7684\u6700\u5927\u751f\u547d\u5468\u671f\u30022MSL\u5373\u662f\u670d\u52a1\u5668\u7aef\u53d1\u51fa\u4e3aFIN\u62a5\u6587\u548c\u5ba2\u6237\u7aef\u53d1\u51fa\u7684ACK\u786e\u8ba4\u62a5\u6587\u6240\u80fd\u4fdd\u6301\u6709\u6548\u7684\u6700\u5927\u65f6\u957f\u3002<\/p>\n<p>\u670d\u52a1\u5668\u7aef\u57281MSL\u5185\u6ca1\u6709\u6536\u5230\u5ba2\u6237\u7aef\u53d1\u51fa\u7684ACK\u786e\u8ba4\u62a5\u6587\uff0c\u5c31\u4f1a\u518d\u6b21\u5411\u5ba2\u6237\u7aef\u53d1\u51faFIN\u62a5\u6587\uff1b<\/p>\n<ul>\n<li>\u5982\u679c\u5ba2\u6237\u7aef\u57282MSL\u5185\uff0c\u518d\u6b21\u6536\u5230\u4e86\u6765\u81ea\u670d\u52a1\u5668\u7aef\u7684FIN\u62a5\u6587\uff0c\u8bf4\u660e\u670d\u52a1\u5668\u7aef\u7531\u4e8e\u5404\u79cd\u539f\u56e0\u6ca1\u6709\u63a5\u6536\u5230\u5ba2\u6237\u7aef\u53d1\u51fa\u7684ACK\u786e\u8ba4\u62a5\u6587\u3002\u5ba2\u6237\u7aef\u518d\u6b21\u5411\u670d\u52a1\u5668\u7aef\u53d1\u51faACK\u786e\u8ba4\u62a5\u6587\uff0c\u8ba1\u65f6\u5668\u91cd\u7f6e\uff0c\u91cd\u65b0\u5f00\u59cb2MSL\u7684\u8ba1\u65f6\uff1b<\/li>\n<li>\u5426\u5219\u5ba2\u6237\u7aef\u57282MSL\u5185\u6ca1\u6709\u518d\u6b21\u6536\u5230\u6765\u81ea\u670d\u52a1\u5668\u7aef\u7684FIN\u62a5\u6587\uff0c\u8bf4\u660e\u670d\u52a1\u5668\u7aef\u6b63\u5e38\u63a5\u6536\u4e86ACK\u786e\u8ba4\u62a5\u6587\uff0c\u5ba2\u6237\u7aef\u53ef\u4ee5\u8fdb\u5165CLOSED\u9636\u6bb5\uff0c\u5b8c\u6210\u201c\u56db\u6b21\u6325\u624b\u201d\u3002<\/li>\n<\/ul>\n<p><strong>\u6240\u4ee5\uff0c\u5ba2\u6237\u7aef\u8981\u7ecf\u5386\u65f6\u957f\u4e3a2SML\u7684TIME-WAIT\u9636\u6bb5\uff1b\u8fd9\u4e5f\u662f\u4e3a\u4ec0\u4e48\u5ba2\u6237\u7aef\u6bd4\u670d\u52a1\u5668\u7aef\u665a\u8fdb\u5165CLOSED\u9636\u6bb5\u7684\u539f\u56e0<\/strong><\/p>\n<h3>6.\u6293\u5305\u9a8c\u8bc1<\/h3>\n<hr \/>\n<p><img src=\"https:\/\/lemon-guess.oss-cn-hangzhou.aliyuncs.com\/1845293-20191213234909815-1157756064.png\" alt=\"\" \/><\/p>\n<p>\u56fe\u4e2d\u663e\u793a\u7684\u5c31\u662f\u5b8c\u6574\u7684TCP\u8fde\u63a5\u91ca\u653e\u7684\u201d\u56db\u6b21\u6325\u624b\u201d\u8fc7\u7a0b\u3002\u5728 80 -&gt; 55389 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href=\"https:\/\/blog.csdn.net\/qq_38950316\/article\/details\/81087809\">TCP\u7684\u4e09\u6b21\u63e1\u624b\u4e0e\u56db\u6b21\u6325\u624b\u7406\u89e3\u53ca\u9762\u8bd5\u9898\uff08\u5f88\u5168\u9762\uff09<\/a><\/p>\n<p><a href=\"https:\/\/www.cnblogs.com\/alva-rabbit-hole\/p\/10081169.html\">\u6df1\u5165\u6d45\u51fa\u56fe\u89e3\u3010\u8ba1\u7b97\u673a\u7f51\u7edc\u3011 \u4e4b \u3010TCP\u53ef\u9760\u4f20\u8f93\u7684\u5b9e\u73b0: \u4e09\u6b21\u63e1\u624b+\u6ed1\u52a8\u7a97\u53e3\u3011<\/a><\/p>\n<p><a href=\"http:\/\/www.bubuko.com\/infodetail-2526697.html\">\u4f7f\u7528 WireShark \u5206\u6790 TCP\/IP \u4e09\u6b21\u63e1\u624b \u548c \u56db\u6b21\u6325\u624b<\/a><\/p>\n<\/blockquote>\n<p>\u672c\u6587\u8f6c\u81ea <a href=\"https:\/\/www.cnblogs.com\/AhuntSun-blog\/p\/12037852.html\">https:\/\/www.cnblogs.com\/AhuntSun-blog\/p\/12037852.html<\/a>\uff0c\u5982\u6709\u4fb5\u6743\uff0c\u8bf7\u8054\u7cfb\u5220\u9664\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e0a\u6587\u94fe\u63a5\uff1a \u8be6\u89e3TCP\u8fde\u63a5\u7684\u201c\u4e09\u6b21\u63e1\u624b\u201d\u4e0e\u201c\u56db\u6b21\u6325\u624b\u201d(\u4e0a) \u56db\u3001TCP\u7684\u56db\u6b21\u6325\u624b\uff08Four-Way Wavehand\uff09 0.\u524d\u8a00 \u5bf9\u4e8e   \u2026 &#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"ngg_post_thumbnail":0},"categories":[73],"tags":[74],"_links":{"self":[{"href":"\/index.php?rest_route=\/wp\/v2\/posts\/1198"}],"collection":[{"href":"\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1198"}],"version-history":[{"count":2,"href":"\/index.php?rest_route=\/wp\/v2\/posts\/1198\/revisions"}],"predecessor-version":[{"id":1200,"href":"\/index.php?rest_route=\/wp\/v2\/posts\/1198\/revisions\/1200"}],"wp:attachment":[{"href":"\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1198"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1198"},{"taxonomy":"post_tag","embeddable":true,"href":"\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1198"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}