{"id":12756,"date":"2026-05-14T11:30:48","date_gmt":"2026-05-14T02:30:48","guid":{"rendered":"https:\/\/sendgrid.kke.co.jp\/blog\/?p=12756"},"modified":"2026-05-14T13:41:05","modified_gmt":"2026-05-14T04:41:05","slug":"starttls%e3%81%a8%e3%81%af%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/sendgrid.kke.co.jp\/blog\/?p=12756","title":{"rendered":"STARTTLS\u3068\u306f\uff1f\u30e1\u30fc\u30eb\u9001\u4fe1\u3092\u6697\u53f7\u5316\u3059\u308b\u4ed5\u7d44\u307f\u3084\u30a8\u30e9\u30fc\u5bfe\u51e6\u6cd5\u3092\u89e3\u8aac\uff01"},"content":{"rendered":"<p><img decoding=\"async\" src=\"https:\/\/sendgrid.kke.co.jp\/blog\/wp\/wp-content\/uploads\/2026\/05\/20260514_blog.png\" alt=\"\" width=\"100%\" class=\"aligncenter size-full wp-image-20783\" srcset=\"https:\/\/sendgrid.kke.co.jp\/blog\/wp\/wp-content\/uploads\/2026\/05\/20260514_blog.png 1200w, https:\/\/sendgrid.kke.co.jp\/blog\/wp\/wp-content\/uploads\/2026\/05\/20260514_blog-300x185.png 300w, https:\/\/sendgrid.kke.co.jp\/blog\/wp\/wp-content\/uploads\/2026\/05\/20260514_blog-1024x630.png 1024w, https:\/\/sendgrid.kke.co.jp\/blog\/wp\/wp-content\/uploads\/2026\/05\/20260514_blog-768x472.png 768w, https:\/\/sendgrid.kke.co.jp\/blog\/wp\/wp-content\/uploads\/2026\/05\/20260514_blog-225x139.png 225w\" sizes=\"(max-width: 1200px) 100vw, 1200px\" \/><\/p>\n<blockquote><p>\u3053\u306e\u8a18\u4e8b\u306f <a href=\"https:\/\/www.twilio.com\/en-us\/blog\/insights\/what-is-starttls\" target=\"_blank\" rel=\"noopener\">What is StartTLS?<\/a> \u306e\u6284\u8a33\u3067\u3059\u3002<\/p><\/blockquote>\n<p>\u30e1\u30fc\u30eb\u304c\u30b5\u30fc\u30d0\u304b\u3089\u30b5\u30fc\u30d0\u3078\u3068\u3069\u306e\u3088\u3046\u306b\u5b89\u5168\u306b\u9001\u4fe1\u3055\u308c\u308b\u306e\u304b\u3001\u7591\u554f\u306b\u601d\u3063\u305f\u3053\u3068\u306f\u3042\u308a\u307e\u305b\u3093\u304b\uff1f<br \/>\n\u30e1\u30fc\u30eb\u9001\u4fe1\u7528\u306e\u30d7\u30ed\u30c8\u30b3\u30eb\u3067\u3042\u308bSMTP\u3067\u306f\u3001STARTTLS\u306b\u3088\u3063\u3066\u901a\u4fe1\u3092TLS\uff08\u307e\u305f\u306fSSL\uff09\u306b\u5207\u308a\u66ff\u3048\u3066\u6697\u53f7\u5316\u3059\u308b\u3053\u3068\u3067\u3001\u30e1\u30fc\u30eb\u3092\u3088\u308a\u5b89\u5168\u306b\u9001\u4fe1\u3067\u304d\u307e\u3059\u3002\uff08\u73fe\u5728\u306f\u4e3b\u306bTLS\u304c\u4f7f\u7528\u3055\u308c\u307e\u3059\uff09<\/p>\n<p>\u3067\u306f\u3001STARTTLS\u3068\u306f\u3069\u306e\u3088\u3046\u306a\u3082\u306e\u3067\u3057\u3087\u3046\u304b\uff1f<\/p>\n<p>STARTTLS\u306f\u3001\u901a\u4fe1\u3092\u6697\u53f7\u5316\u3059\u308b\u305f\u3081\u306b\u4f7f\u7528\u3055\u308c\u308b\u30b3\u30de\u30f3\u30c9\u3067\u3059\u3002\u6697\u53f7\u5316\u3055\u308c\u3066\u3044\u306a\u3044\u63a5\u7d9a\u3092TLS\u307e\u305f\u306fSSL\u306b\u3088\u308b\u6697\u53f7\u5316\u63a5\u7d9a\u3078\u5207\u308a\u66ff\u3048\u305f\u3044\u65e8\u3092\u3001\u63a5\u7d9a\u5148\u306e\u30b5\u30fc\u30d0\u306b\u901a\u77e5\u3059\u308b\u969b\u306b\u4f7f\u7528\u3055\u308c\u307e\u3059\u3002STARTTLS\u306fSMTP\u3068IMAP\u3067\u4f7f\u7528\u3055\u308c\u3001POP3\u3067\u306f\u540c\u69d8\u306e\u76ee\u7684\u3067STLS\u3068\u547c\u3070\u308c\u308b\u5c11\u3057\u7570\u306a\u308b\u30b3\u30de\u30f3\u30c9\u304c\u4f7f\u7528\u3055\u308c\u307e\u3059\u3002<\/p>\n<p>\u4eca\u56de\u306f\u3001STARTTLS\u3068TLS\u306e\u9055\u3044\u3084STARTTLS\u306e\u4ed5\u7d44\u307f\u3001\u305d\u3057\u3066STARTTLS\u63a5\u7d9a\u306e\u30c8\u30e9\u30d6\u30eb\u30b7\u30e5\u30fc\u30c6\u30a3\u30f3\u30b0\u306b\u3064\u3044\u3066\u8a73\u3057\u304f\u7d39\u4ecb\u3057\u307e\u3059\u3002<\/p>\n<h3>STARTTLS\u3068TLS\u306e\u9055\u3044<\/h3>\n<p>STARTTLS\u3068TLS\u306f\u7af6\u5408\u3059\u308b\u3082\u306e\u3067\u306f\u306a\u304f\u3001\u9023\u643a\u3057\u3066\u52d5\u4f5c\u3057\u307e\u3059\u3002TLS\u306f\u5b9f\u969b\u306b\u30c7\u30fc\u30bf\u3092\u4fdd\u8b77\u3059\u308b\u6697\u53f7\u5316\u30d7\u30ed\u30c8\u30b3\u30eb\u3067\u3042\u308a\u3001STARTTLS\u306f\u305d\u306e\u6697\u53f7\u5316\u51e6\u7406\u3092\u958b\u59cb\u3059\u308b\u305f\u3081\u306e\u30b3\u30de\u30f3\u30c9\u3067\u3059\u3002<\/p>\n<p>STARTTLS\u306e\u7279\u5fb4\u306f\u4ee5\u4e0b\u306e\u3068\u304a\u308a\u3067\u3059\u3002<\/p>\n<ul>\n<li>\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u3068\u30b5\u30fc\u30d0\u306e\u9593\u3067\u3001\u6697\u53f7\u5316\u3055\u308c\u3066\u3044\u306a\u3044\u63a5\u7d9a\u3092\u6697\u53f7\u5316\u63a5\u7d9a\u3078\u5207\u308a\u66ff\u3048\u308b\u305f\u3081\u306b\u4f7f\u7528\u3055\u308c\u308b<\/li>\n<li>TLS\u304a\u3088\u3073\u53e4\u3044\u898f\u683c\u3067\u3042\u308bSSL\u306e\u4e21\u65b9\u306b\u5bfe\u5fdc\u3057\u3066\u3044\u308b<\/li>\n<\/ul>\n<p>TLS\u306e\u7279\u5fb4\u306f\u4ee5\u4e0b\u306e\u3068\u304a\u308a\u3067\u3059\u3002<\/p>\n<ul>\n<li>\u9001\u53d7\u4fe1\u3055\u308c\u308b\u30c7\u30fc\u30bf\u3092\u6697\u53f7\u5316\u3057\u3001\u30e1\u30fc\u30eb\u306e\u30b3\u30f3\u30c6\u30f3\u30c4\u3092\u4fdd\u8b77\u3059\u308b<\/li>\n<li>TLS 1.0\u30011.1\u30011.2\u30011.3\u3068\u3044\u3063\u305f\u8907\u6570\u306e\u30d0\u30fc\u30b8\u30e7\u30f3\u304c\u5b58\u5728\u3059\u308b\uff08TLS 1.0\u30681.1\u306f\u73fe\u5728\u975e\u63a8\u5968\uff09<\/li>\n<li>STARTTLS\u30b3\u30de\u30f3\u30c9\u306e\u6709\u7121\u306b\u95a2\u308f\u3089\u305a\u5229\u7528\u3067\u304d\u308b<\/li>\n<\/ul>\n<p>STARTTLS\u3067\u3042\u308c\u3070\u3001\u6697\u53f7\u5316\u3055\u308c\u305f\u63a5\u7d9a\u3068\u6697\u53f7\u5316\u3055\u308c\u3066\u3044\u306a\u3044\u63a5\u7d9a\u306e\u4e21\u65b9\u3092\u540c\u3058\u30dd\u30fc\u30c8\u3067\u51e6\u7406\u3067\u304d\u308b\u305f\u3081\u3001\u67d4\u8edf\u306a\u30e1\u30fc\u30eb\u306e\u904b\u7528\u304c\u53ef\u80fd\u3067\u3059\u3002\u4e00\u65b9\u3001STARTTLS\u3092\u4f7f\u308f\u306a\u3044\u5834\u5408\u306f\u3001\u5b89\u5168\u306a\u901a\u4fe1\u3068\u305d\u3046\u3067\u306a\u3044\u901a\u4fe1\u3067\u305d\u308c\u305e\u308c\u5225\u306e\u30dd\u30fc\u30c8\u3092\u7528\u610f\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002\u3053\u308c\u306f\u3001465\u756a\u30dd\u30fc\u30c8\u3092\u4f7f\u7528\u3059\u308b\u6697\u9ed9\u7684TLS\u3067\u63a1\u7528\u3055\u308c\u3066\u3044\u308b\u65b9\u5f0f\u3067\u3059\u3002<\/p>\n<p>Twilio SendGrid\u306eTLS\u901a\u4fe1\u306b\u3064\u3044\u3066\u306f<a href=\"https:\/\/www.twilio.com\/docs\/sendgrid\/concepts\/security\/tls\" rel=\"noopener\" target=\"_blank\">\u3053\u3061\u3089<\/a>\u3067\u3082\u7d39\u4ecb\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n<h3>STARTTLS\u306e\u4ed5\u7d44\u307f<\/h3>\n<p>STARTTLS\u306b\u3088\u308b\u6697\u53f7\u5316\u30d7\u30ed\u30bb\u30b9\u3092\u5177\u4f53\u7684\u306b\u898b\u3066\u3044\u304d\u307e\u3057\u3087\u3046\u3002<br \/>\nSMTP\u901a\u4fe1\u306f\u6bce\u56de\u6697\u53f7\u5316\u3055\u308c\u3066\u3044\u306a\u3044\u72b6\u614b\u3067\u958b\u59cb\u3055\u308c\u3001STARTTLS\u30b3\u30de\u30f3\u30c9\u3092\u304d\u3063\u304b\u3051\u306b\u30b5\u30fc\u30d0\u3068\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u9593\u306e\u30cd\u30b4\u30b7\u30a8\u30fc\u30b7\u30e7\u30f3\u304c\u59cb\u307e\u308a\u307e\u3059\u3002\u305d\u306e\u969b\u306e\u901a\u4fe1\u306e\u6982\u8981\u306f\u4ee5\u4e0b\u306e\u3068\u304a\u308a\u3067\u3059\u3002<\/p>\n<ol>\n<li>\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u3068\u30b5\u30fc\u30d0\u304c\u304a\u4e92\u3044\u3092\u8a8d\u8b58\u3059\u308b\u305f\u3081\u306b\u3001TCP\u30cf\u30f3\u30c9\u30b7\u30a7\u30a4\u30af\u3092\u884c\u3044\u307e\u3059\u3002<\/li>\n<li>\u30b5\u30fc\u30d0\u306f\u300c220 Ready\u300d\u3092\u8fd4\u3057\u3001\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u306b\u5bfe\u3057\u3066\u901a\u4fe1\u3092\u7d9a\u884c\u3067\u304d\u308b\u3053\u3068\u3092\u901a\u77e5\u3057\u307e\u3059\u3002<\/li>\n<li>\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u306f\u300cEHLO\u300d\u3092\u9001\u4fe1\u3057\u3001ESMTP\uff08\u753b\u50cf\u3084\u6dfb\u4ed8\u30d5\u30a1\u30a4\u30eb\u306a\u3069\u3092\u6271\u3048\u308b\u62e1\u5f35\u7248SMTP\uff09\u3092\u4f7f\u7528\u3059\u308b\u3053\u3068\u3092\u30b5\u30fc\u30d0\u3078\u4f1d\u3048\u307e\u3059\u3002<\/li>\n<li>\u30b5\u30fc\u30d0\u306f\u300c250-STARTTLS\u300d\u3092\u8fd4\u3057\u3001\u81ea\u8eab\u304cSTARTTLS\u306b\u5bfe\u5fdc\u3057\u3066\u3044\u308b\u3053\u3068\u3092\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u306b\u901a\u77e5\u3057\u307e\u3059\u3002<\/li>\n<li>\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u306f\u300cSTARTTLS\u300d\u3092\u9001\u4fe1\u3057\u3001\u6697\u53f7\u5316\u3092\u8981\u6c42\u3057\u307e\u3059\u3002<\/li>\n<li>\u30b5\u30fc\u30d0\u306f\u300c220 Go ahead\u300d\u306a\u3069\u306e\u5fdc\u7b54\u3092\u8fd4\u3057\u3001\u4ee5\u964d\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u3068\u30b5\u30fc\u30d0\u9593\u3067TLS\u30cd\u30b4\u30b7\u30a8\u30fc\u30b7\u30e7\u30f3\u304c\u59cb\u307e\u308a\u307e\u3059\u3002TLS\u306e\u30d0\u30fc\u30b8\u30e7\u30f3\u306f\u3001\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u3068\u30b5\u30fc\u30d0\u306e\u53cc\u65b9\u304c\u5bfe\u5fdc\u3057\u3066\u3044\u308b\u30d0\u30fc\u30b8\u30e7\u30f3\u306e\u3046\u3061\u6700\u3082\u9ad8\u3044\u3082\u306e\u304c\u4f7f\u7528\u3055\u308c\u307e\u3059\u3002\u30cd\u30b4\u30b7\u30a8\u30fc\u30b7\u30e7\u30f3\u304c\u884c\u308f\u308c\u308b\u9593\u3001SMTP\u901a\u4fe1\u306f\u4e00\u6642\u505c\u6b62\u3055\u308c\u307e\u3059\u3002<\/li>\n<li>TLS\u30cd\u30b4\u30b7\u30a8\u30fc\u30b7\u30e7\u30f3\u304c\u5b8c\u4e86\u3057\u305f\u5f8c\u3001\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u304cSMTP\u901a\u4fe1\u3092\u518d\u958b\u3057\u307e\u3059\u3002\u4ee5\u964d\u306e\u30e1\u30fc\u30eb\u901a\u4fe1\u306f\u6697\u53f7\u5316\u3055\u308c\u305f\u72b6\u614b\u3067\u884c\u308f\u308c\u307e\u3059\u3002<\/li>\n<\/ol>\n<p><img decoding=\"async\" src=\"https:\/\/sendgrid.kke.co.jp\/blog\/wp\/wp-content\/uploads\/2026\/05\/image2.jpg\" alt=\"STARTTLS\u306b\u3088\u308b\u6697\u53f7\u5316\u30d7\u30ed\u30bb\u30b9\" width=\"100%\" class=\"aligncenter size-full wp-image-20784\" srcset=\"https:\/\/sendgrid.kke.co.jp\/blog\/wp\/wp-content\/uploads\/2026\/05\/image2.jpg 960w, https:\/\/sendgrid.kke.co.jp\/blog\/wp\/wp-content\/uploads\/2026\/05\/image2-300x169.jpg 300w, https:\/\/sendgrid.kke.co.jp\/blog\/wp\/wp-content\/uploads\/2026\/05\/image2-768x432.jpg 768w\" sizes=\"(max-width: 960px) 100vw, 960px\" \/><\/p>\n<h4>\u4f7f\u7528\u3059\u308b\u30dd\u30fc\u30c8\u306f\uff1f<\/h4>\n<p>STARTTLS\u3067\u306f\u3001587\u756a\u30dd\u30fc\u30c8\u304c\u6700\u3082\u4f7f\u7528\u3055\u308c\u307e\u3059\u3002\u4ed6\u306b\u3082\u3001\u6697\u53f7\u5316\u3055\u308c\u305f\u30e1\u30fc\u30eb\u3092\u9001\u4fe1\u3059\u308b\u305f\u3081\u306b\u300125\u3001465\u3001\u304a\u3088\u30732525\u306a\u3069\u306e\u30dd\u30fc\u30c8\u304c\u4f7f\u7528\u3055\u308c\u307e\u3059\u300225\u756a\u30dd\u30fc\u30c8\u306f\u30b5\u30fc\u30d0\u9593\u306e\u30e1\u30fc\u30eb\u8ee2\u9001\u3067\u4f7f\u7528\u3059\u308b\u3082\u306e\u3067\u3042\u308a\u3001\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u304b\u3089\u306e\u9001\u4fe1\u7528\u3067\u306f\u306a\u3044\u305f\u3081\u3001ISP\u306f\u3053\u306e\u30dd\u30fc\u30c8\u3092\u4ecb\u3057\u3066\u9001\u4fe1\u3055\u308c\u305f\u30e1\u30fc\u30eb\u3092\u30d6\u30ed\u30c3\u30af\u3059\u308b\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002\u307e\u305f\u3001587\u756a\u30dd\u30fc\u30c8\u306e\u6b21\u306b\u4f7f\u7528\u983b\u5ea6\u304c\u9ad8\u3044\u306e\u306f465\u756a\u30dd\u30fc\u30c8\u3067\u3059\u3002<\/p>\n<h4>\u65e5\u548c\u898bTLS vs. \u5f37\u5236TLS<\/h4>\n<p>\u30e1\u30fc\u30eb\u3092\u6697\u53f7\u5316\u3057\u3066\u9001\u4fe1\u3059\u308b\u306b\u306f\u3001\u65e5\u548c\u898bTLS\u307e\u305f\u306f\u5f37\u5236TLS\u306e\u3044\u305a\u308c\u304b\u3092\u5229\u7528\u3057\u307e\u3059\u3002<\/p>\n<p>\u65e5\u548c\u898bTLS\uff08\u307e\u305f\u306f\u660e\u793a\u7684TLS\uff09\u3092\u5229\u7528\u3059\u308b\u3068\u3001\u30b5\u30fc\u30d0\u304c\u53d7\u3051\u5165\u308c\u308b\u6700\u9ad8\u306e\u6697\u53f7\u5316\u30ec\u30d9\u30eb\u3067\u9001\u4fe1\u3067\u304d\u307e\u3059\u3002\u30b5\u30fc\u30d0\u304cTLS\u306b\u5bfe\u5fdc\u3057\u3066\u3044\u306a\u3044\u5834\u5408\u3001\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u306f\u30b5\u30fc\u30d0\u3068\u30cd\u30b4\u30b7\u30a8\u30fc\u30c8\u3057\u3001\u6697\u53f7\u5316\u3055\u308c\u3066\u3044\u306a\u3044\u63a5\u7d9a\u306b\u30c0\u30a6\u30f3\u30b0\u30ec\u30fc\u30c9\u3059\u308b\u3053\u3068\u306b\u5408\u610f\u3057\u307e\u3059\u3002\u5408\u610f\u306b\u9054\u3059\u308b\u3068\u3001\u30e1\u30c3\u30bb\u30fc\u30b8\u306f\u6697\u53f7\u5316\u3055\u308c\u305a\u306b\u9001\u4fe1\u3055\u308c\u307e\u3059\u3002\u3053\u306e\u65b9\u5f0f\u306b\u306f\u3001\u6697\u53f7\u5316\u3055\u308c\u305f\u30e1\u30fc\u30eb\u3068\u6697\u53f7\u5316\u3055\u308c\u306a\u3044\u30e1\u30fc\u30eb\u4e21\u65b9\u3067\u540c\u3058\u30dd\u30fc\u30c8\u3092\u4f7f\u7528\u3067\u304d\u308b\u5229\u70b9\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n<p>\u4e00\u65b9\u3001\u5f37\u5236TLS\uff08\u307e\u305f\u306f\u6697\u9ed9\u7684TLS\uff09\u306f\u3001\u5b89\u5168\u306a\u63a5\u7d9a\u3067\u30e1\u30fc\u30eb\u3092\u9001\u4fe1\u3059\u308b\u3053\u3068\u3092\u8981\u6c42\u3057\u307e\u3059\u3002\u63a5\u7d9a\u304c\u6697\u53f7\u5316\u3055\u308c\u3066\u3044\u306a\u3044\u5834\u5408\u3001\u30e1\u30fc\u30eb\u306f\u9001\u4fe1\u3055\u308c\u307e\u305b\u3093\u3002\u3053\u306e\u65b9\u6cd5\u306f\u65e5\u548c\u898bTLS\u3088\u308a\u3082\u306f\u308b\u304b\u306b\u5b89\u5168\u3067\u3059\u304c\u3001\u3088\u308a\u591a\u304f\u306e\u30e1\u30fc\u30eb\u304c\u7834\u68c4\u3055\u308c\u308b\u3053\u3068\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n<p>\u3069\u3061\u3089\u306e\u65b9\u5f0f\u3082\u30e1\u30fc\u30eb\u306e\u4e16\u754c\u3067\u306f\u5e83\u304f\u4f7f\u308f\u308c\u3066\u3044\u307e\u3059\u3002\u6a5f\u5bc6\u6027\u306e\u9ad8\u3044\u500b\u4eba\u60c5\u5831\u3092\u542b\u3080\u30e1\u30fc\u30eb\u3092\u9001\u4fe1\u3059\u308b\u5834\u5408\u306f\u3001\u5f37\u5236TLS\u3092\u4f7f\u7528\u3059\u308b\u306e\u304c\u30d9\u30b9\u30c8\u304b\u3082\u3057\u308c\u307e\u305b\u3093\u3002\u4e00\u65b9\u3001\u30de\u30fc\u30b1\u30c6\u30a3\u30f3\u30b0\u3084\u30d7\u30ed\u30e2\u30fc\u30b7\u30e7\u30f3\u30e1\u30fc\u30eb\u306e\u3088\u3046\u306a\u30bb\u30f3\u30b7\u30c6\u30a3\u30d6\u3067\u306a\u3044\u5185\u5bb9\u3092\u9001\u4fe1\u3059\u308b\u5834\u5408\u306f\u3001\u65e5\u548c\u898bTLS\u3092\u4f7f\u7528\u3059\u308b\u306e\u304c\u826f\u3044\u3067\u3057\u3087\u3046\u3002<\/p>\n<h4>\u305d\u306e\u4ed6\u306eTLS\u306e\u30e6\u30fc\u30b9\u30b1\u30fc\u30b9<\/h4>\n<p>TLS\u306f\u3001\u30e1\u30fc\u30eb\u4ee5\u5916\u306e\u901a\u4fe1\u306e\u6697\u53f7\u5316\u306b\u3082\u4f7f\u308f\u308c\u3066\u3044\u307e\u3059\u3002TLS\u306f\u6bd4\u8f03\u7684\u30b7\u30f3\u30d7\u30eb\u304b\u3064\u591a\u6bb5\u968e\u306e\u30d7\u30ed\u30c8\u30b3\u30eb\u3067\u3042\u308b\u305f\u3081\u3001Web\u30d6\u30e9\u30a6\u30b6\u3084SMS\u3001VoIP\u306a\u3069\u3001\u3055\u307e\u3056\u307e\u306a\u901a\u4fe1\u306b\u5bb9\u6613\u306b\u5bfe\u5fdc\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002\u5b9f\u969b\u3001\u591a\u304f\u306e\u4f01\u696d\u3067\u306f\u3001\u901a\u4fe1\u306e\u5927\u90e8\u5206\u304c\u6a5f\u5bc6\u4e8b\u9805\u3067\u306a\u304f\u3066\u3082\u3001TLS\u3092\u4f7f\u7528\u3057\u3066Web\u30b5\u30fc\u30d0\u3068\u30d6\u30e9\u30a6\u30b6\u9593\u306e\u3059\u3079\u3066\u306e\u901a\u4fe1\u3092\u6697\u53f7\u5316\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n<p>Twilio\u304cTLS\u3092\u3069\u306e\u3088\u3046\u306b\u4f7f\u7528\u3057\u3066\u3044\u308b\u304b\u306e\u8a73\u7d30\u306b\u3064\u3044\u3066\u306f\u3001<a href=\"https:\/\/www.twilio.com\/docs\/usage\/security\" rel=\"noopener\" target=\"_blank\">Twilio\u306e\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u30da\u30fc\u30b8<\/a>\u3092\u3054\u89a7\u304f\u3060\u3055\u3044\u3002<\/p>\n<h3>STARTTLS\u304c\u306a\u305c\u91cd\u8981\u306a\u306e\u304b\uff1f<\/h3>\n<p>\u5143\u3005SMTP\u306f\u5b89\u5168\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002STARTTLS\u3092\u4f7f\u7528\u305b\u305a\u306bSMTP\u3067\u30e1\u30fc\u30eb\u9001\u4fe1\u3059\u308b\u3068\u3001\u508d\u53d7\u3055\u308c\u3001\u7c21\u5358\u306b\u89e3\u8aad\u3055\u308c\u3066\u3057\u307e\u3046\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002\u30e6\u30fc\u30b6\u540d\u3084\u30d1\u30b9\u30ef\u30fc\u30c9\u3001\u9280\u884c\u306e\u60c5\u5831\u306a\u3069\u6a5f\u5bc6\u6027\u306e\u9ad8\u3044\u500b\u4eba\u60c5\u5831\u3092\u9001\u4fe1\u3059\u308b\u5834\u5408\u306b\u306f\u7279\u306b\u6ce8\u610f\u304c\u5fc5\u8981\u3067\u3059\u3002<\/p>\n<p>\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u304cSTARTTLS\u3092\u4f7f\u7528\u3059\u308b\u3068\u3001\u30e1\u30c3\u30bb\u30fc\u30b8\u306f\u6697\u53f7\u5316\u3055\u308c\u3066\u9001\u4fe1\u3055\u308c\u307e\u3059\u3002\u4eee\u306b\u508d\u53d7\u3055\u308c\u3066\u3082\u89e3\u8aad\u306f\u975e\u5e38\u306b\u56f0\u96e3\u3067\u3059\u3002\u30e1\u30c3\u30bb\u30fc\u30b8\u3092\u89e3\u8aad\u3059\u308b\u305f\u3081\u306e\u9375\u3092\u6301\u3063\u3066\u3044\u308b\u306e\u306f\u3001\u30b5\u30fc\u30d0\u3068\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u3060\u3051\u3067\u3059\u3002<\/p>\n<h4>\u6b20\u70b9<\/h4>\n<p>STARTTLS\u306b\u306f\u3044\u304f\u3064\u304b\u306e\u6b20\u70b9\u3082\u3042\u308a\u307e\u3059\u3002\u307e\u305a\u3001\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u3068\u30b5\u30fc\u30d0\u9593\u306e\u6700\u521d\u306e\u63a5\u7d9a\u3067\u306f\u3001IP\u30a2\u30c9\u30ec\u30b9\u304c\u6697\u53f7\u5316\u3055\u308c\u3066\u3044\u306a\u3044\u305f\u3081\u3001\u4e2d\u9593\u8005\u653b\u6483\u306e\u5f71\u97ff\u3092\u53d7\u3051\u3084\u3059\u3044\u70b9\u3067\u3059\u3002<\/p>\n<p>\u307e\u305f\u3001STARTTLS\u3092\u4f7f\u308f\u306a\u3044SMTP\u63a5\u7d9a\u3068\u6bd4\u3079\u3066\u3001\u82e5\u5e72\u306e\u9045\u5ef6\u304c\u767a\u751f\u3059\u308b\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002\u4f7f\u3044\u7269\u306b\u306a\u3089\u306a\u3044\u307b\u3069\u306e\u9045\u5ef6\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u304c\u3001\u3042\u308b\u7a0b\u5ea6\u306e\u5f71\u97ff\u304c\u3042\u308b\u3053\u3068\u3092\u899a\u3048\u3066\u304a\u304f\u3068\u826f\u3044\u3067\u3057\u3087\u3046\u3002<\/p>\n<h3>STARTTLS\u306e\u5bfe\u5fdc\u72b6\u6cc1\u3092\u78ba\u8a8d\u3059\u308b\u65b9\u6cd5<\/h3>\n<p>\u30b5\u30fc\u30d0\u304cSTARTTLS\u306b\u5bfe\u5fdc\u3057\u3066\u3044\u308b\u304b\u3069\u3046\u304b\u3092\u4e8b\u524d\u306b\u78ba\u8a8d\u3057\u3066\u304a\u304f\u3053\u3068\u306f\u91cd\u8981\u3067\u3059\u3002STARTTLS\u306b\u5bfe\u5fdc\u3057\u3066\u3044\u306a\u3044\u5834\u5408\u3001\u610f\u56f3\u305b\u305a\u6697\u53f7\u5316\u3055\u308c\u3066\u3044\u306a\u3044\u30e1\u30fc\u30eb\u3092\u5927\u91cf\u9001\u4fe1\u3057\u3066\u3057\u307e\u3044\u3001\u305d\u306e\u7d50\u679c\u3001\u653b\u6483\u306e\u6a19\u7684\u306b\u3055\u308c\u3066\u3057\u307e\u3046\u6050\u308c\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n<p>\u4ee5\u4e0b\u306f\u3001SendGrid\u306eSMTP\u30b5\u30fc\u30d0\u3067STARTTLS\u306e\u5bfe\u5fdc\u72b6\u6cc1\u3092\u78ba\u8a8d\u3059\u308b\u65b9\u6cd5\u306e\u4f8b\u3067\u3059\u3002\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u304b\u3089EHLO\u3092\u9001\u4fe1\u3057\u305f\u5f8c\u3001\u30b5\u30fc\u30d0\u304b\u3089\u306e\u5fdc\u7b54\u306b\u300c250-STARTTLS\u300d\u304c\u542b\u307e\u308c\u3066\u3044\u308c\u3070\u3001\u305d\u306e\u30b5\u30fc\u30d0\u304cSTARTTLS\u306b\u5bfe\u5fdc\u3057\u3066\u3044\u308b\u3053\u3068\u304c\u5206\u304b\u308a\u307e\u3059\u3002<\/p>\n<pre class=\"brush: bash; title: ; notranslate\" title=\"\">\r\n&gt; telnet smtp.sendgrid.net 587\r\nTrying 167.89.118.58...\r\nConnected to smtp.sendgrid.net.\r\nEscape character is &#039;^]&#039;.\r\n220 SG ESMTP service ready at geopod-ismtpd-13\r\n&gt; EHLO\r\n250-smtp.sendgrid.net\r\n250-8BITMIME\r\n250-PIPELINING\r\n250-SIZE 31457280\r\n250-STARTTLS\r\n250-AUTH PLAIN LOGIN\r\n250 AUTH=PLAIN LOGIN\r\n<\/pre>\n<h3>\u30c8\u30e9\u30d6\u30eb\u30b7\u30e5\u30fc\u30c6\u30a3\u30f3\u30b0<\/h3>\n<p>\u30a8\u30e9\u30fc\u306b\u906d\u9047\u3059\u308b\u306e\u306f\u907f\u3051\u305f\u3044\u3068\u3053\u308d\u3067\u3059\u304c\u3001\u539f\u56e0\u304c\u308f\u304b\u308c\u3070\u6bd4\u8f03\u7684\u7c21\u5358\u306b\u5bfe\u51e6\u3067\u304d\u307e\u3059\u3002<\/p>\n<ul>\n<li><strong>\u30a8\u30e9\u30fc\u300cMust issue a STARTTLS command first\u300d<\/strong><br \/>\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u304c\u3001\u6697\u53f7\u5316\u901a\u4fe1\u3092\u78ba\u7acb\u3059\u308b\u3088\u308a\u3082\u524d\u306b\u8a8d\u8a3c\u3092\u8a66\u307f\u3066\u3044\u307e\u3059\u3002<br \/>\u5bfe\u51e6\u6cd5\uff1a<br \/>\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u306e\u8a2d\u5b9a\u3067STARTTLS\u3092\u6709\u52b9\u306b\u3057\u3066\u304f\u3060\u3055\u3044\u3002\u307e\u305f\u3001\u6b63\u3057\u3044\u30dd\u30fc\u30c8\uff08\u901a\u5e38\u306f587\u756a\uff09\u3092\u4f7f\u7528\u3057\u3066\u3044\u308b\u304b\u78ba\u8a8d\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/li>\n<li><strong>\u30a8\u30e9\u30fc\u300cSTARTTLS is required\u300d<\/strong><br \/>\u63a5\u7d9a\u5148\u306e\u30b5\u30fc\u30d0\u3067\u306f\u6697\u53f7\u5316\u304c\u5fc5\u9808\u3067\u3059\u304c\u3001\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u304c\u6697\u53f7\u5316\u3092\u8981\u6c42\u3057\u3066\u3044\u307e\u305b\u3093\u3002<br \/>\u5bfe\u51e6\u6cd5\uff1a<br \/>SMTP\u8a2d\u5b9a\u3067\u3001SSL\/TLS\u3060\u3051\u3067\u306a\u304fSTARTTLS\u3082\u6709\u52b9\u306b\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/li>\n<li><strong>\u63a5\u7d9a\u30bf\u30a4\u30e0\u30a2\u30a6\u30c8\u307e\u305f\u306f\u63a5\u7d9a\u62d2\u5426\uff08Connection timed out\u3001Connection refused\u306a\u3069\uff09<\/strong><br \/>\u4f7f\u7528\u3057\u3066\u3044\u308bSMTP\u30dd\u30fc\u30c8\u304cISP\u306b\u3088\u3063\u3066\u30d6\u30ed\u30c3\u30af\u3055\u308c\u3066\u3044\u308b\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002\u7279\u306b25\u756a\u30dd\u30fc\u30c8\u3067\u63a5\u7d9a\u306b\u5931\u6557\u3059\u308b\u5834\u5408\u306f\u3001ISP\u306b\u3088\u308b\u30d6\u30ed\u30c3\u30af\u304c\u539f\u56e0\u3060\u3068\u8003\u3048\u3089\u308c\u307e\u3059\u3002<br \/>\u5bfe\u51e6\u6cd5\uff1a<br \/>\u4ed6\u306e\u30dd\u30fc\u30c8\uff08587\u756a\u30012525\u756a\u3001465\u756a\uff09\u3092\u4f7f\u7528\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/li>\n<li><strong>\u8a3c\u660e\u66f8\u306e\u691c\u8a3c\u5931\u6557\uff08Certificate verification failed\u306a\u3069\uff09<\/strong><br \/>\u30b5\u30fc\u30d0\u306eTLS\u8a3c\u660e\u66f8\u3092\u691c\u8a3c\u3067\u304d\u307e\u305b\u3093\u3067\u3057\u305f\u3002<br \/>\u5bfe\u51e6\u6cd5\uff1a<br \/>\u4f7f\u7528\u3057\u3066\u3044\u308b\u7aef\u672b\u306e\u65e5\u6642\u8a2d\u5b9a\u304c\u6b63\u3057\u3044\u304b\u3001\u307e\u305f\u3001\u30b5\u30fc\u30d0\u306e\u30db\u30b9\u30c8\u540d\u304c\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u5074\u306eSMTP\u8a2d\u5b9a\u3068\u5b8c\u5168\u306b\u4e00\u81f4\u3057\u3066\u3044\u308b\u304b\u78ba\u8a8d\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/li>\n<li><strong>\u30cd\u30b4\u30b7\u30a8\u30fc\u30b7\u30e7\u30f3\u5931\u6557\uff08Negotiation failed\u306a\u3069\uff09<\/strong><br \/>\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u3068\u30b5\u30fc\u30d0\u306e\u9593\u3067\u3001\u5229\u7528\u3067\u304d\u308bTLS\u306e\u30d0\u30fc\u30b8\u30e7\u30f3\u304c\u4e00\u81f4\u3057\u3066\u3044\u307e\u305b\u3093\u3002<br \/>\u5bfe\u51e6\u6cd5\uff1a<br \/>\u30b5\u30fc\u30d0\u304c\u5bfe\u5fdc\u3057\u3066\u3044\u308bTLS\u306e\u30d0\u30fc\u30b8\u30e7\u30f3\u3092\u78ba\u8a8d\u3057\u3001\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u3092\u66f4\u65b0\u3057\u3066\u304f\u3060\u3055\u3044\u3002\u53e4\u3044\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u3067\u306f\u3001\u65e2\u306b\u975e\u63a8\u5968\uff08deprecated\uff09\u3068\u306a\u3063\u3066\u3044\u308b\u30d0\u30fc\u30b8\u30e7\u30f3\u306b\u3057\u304b\u5bfe\u5fdc\u3057\u3066\u3044\u306a\u3044\u5834\u5408\u304c\u3042\u308a\u307e\u3059\u3002<\/li>\n<\/ul>\n<p>\u30a8\u30e9\u30fc\u306b\u5bfe\u51e6\u3059\u308b\u969b\u306f\u3001\u4ee5\u4e0b\u306e\u9806\u5e8f\u3067\u78ba\u8a8d\u3059\u308b\u306e\u304c\u304a\u3059\u3059\u3081\u3067\u3059\u3002<\/p>\n<ol>\n<li><a href=\"https:\/\/sendgrid.kke.co.jp\/docs\/Tutorials\/A_Transaction_Mail\/send_transaction_mail.html#-Telnet\" rel=\"noopener\" target=\"_blank\">Telnet<\/a>\u3067STARTTLS\u63a5\u7d9a\u3092\u884c\u3044\u3001\u30b5\u30fc\u30d0\u304cSTARTTLS\u306b\u5bfe\u5fdc\u3057\u3066\u3044\u308b\u3053\u3068\u3092\u78ba\u8a8d\u3059\u308b\uff08\u4e0a\u8ff0\u306e\u300cSTARTTLS\u306e\u5bfe\u5fdc\u72b6\u6cc1\u3092\u78ba\u8a8d\u3059\u308b\u65b9\u6cd5\u300d\u3092\u53c2\u7167\uff09<\/li>\n<li>SMTP\u30b5\u30fc\u30d0\u306e\u30a2\u30c9\u30ec\u30b9\u3068\u30dd\u30fc\u30c8\u306e\u7d44\u307f\u5408\u308f\u305b\u304c\u6b63\u3057\u3044\u3053\u3068\u3092\u78ba\u8a8d\u3059\u308b<\/li>\n<li>\u30d5\u30a1\u30a4\u30a2\u30a6\u30a9\u30fc\u30eb\u3084\u30a6\u30a4\u30eb\u30b9\u5bfe\u7b56\u30bd\u30d5\u30c8\u304cSMTP\u63a5\u7d9a\u306b\u5f71\u97ff\u3057\u3066\u3044\u306a\u3044\u304b\u78ba\u8a8d\u3059\u308b<\/li>\n<li>\u63a5\u7d9a\u5148\u306e\u30dd\u30fc\u30c8\u304cSTARTTLS\u3092\u30b5\u30dd\u30fc\u30c8\u3057\u3066\u3044\u308b\u304b\u78ba\u8a8d\u3059\u308b<\/li>\n<\/ol>\n<p>\u4e0a\u8a18\u3092\u8a66\u3057\u3066\u3082\u554f\u984c\u304c\u89e3\u6c7a\u3057\u306a\u3044\u5834\u5408\u3001\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u306e\u8a2d\u5b9a\u306b\u554f\u984c\u304c\u3042\u308b\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002\u8a8d\u8a3c\u65b9\u6cd5\u3084\u30dd\u30fc\u30c8\u756a\u53f7\u304c\u6b63\u3057\u3044\u304b\u3092\u78ba\u8a8d\u3057\u3001SSL\/TLS\u3060\u3051\u3067\u306a\u304fSTARTTLS\u304c\u660e\u793a\u7684\u306b\u6709\u52b9\u306b\u306a\u3063\u3066\u3044\u308b\u3053\u3068\u3092\u78ba\u8a8d\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n<h3>SendGrid\u306b\u304a\u3051\u308bSTARTTLS\u306e\u5229\u7528<\/h3>\n<p>SendGrid\u306fTLS 1.2\u4ee5\u4e0a\u3092\u30b5\u30dd\u30fc\u30c8\u3057\u3066\u3044\u307e\u3059\u3002\u975e\u6697\u53f7\u5316\u304a\u3088\u3073TLS\u63a5\u7d9a\u306f\u30dd\u30fc\u30c825\u3001587\u30012525\u3067\u53d7\u3051\u4ed8\u3051\u3066\u3044\u307e\u3059\u3002465\u756a\u30dd\u30fc\u30c8\u3067\u306eSSL\u63a5\u7d9a\u3082\u53ef\u80fd\u3067\u3059\u3002<\/p>\n<p>\u307e\u305f\u3001\u65e5\u548c\u898bTLS\u3084\u5f37\u5236TLS\u306b\u3082\u5bfe\u5fdc\u3057\u3066\u3044\u307e\u3059\u3002\u65e5\u548c\u898bTLS\u3067\u306f\u3001\u5b9b\u5148\u30b5\u30fc\u30d0\u304c\u5bfe\u5fdc\u3057\u3066\u3044\u308b\u4e2d\u3067\u6700\u3082\u9ad8\u3044\u6697\u53f7\u5316\u30ec\u30d9\u30eb\u3067\u30e1\u30fc\u30eb\u3092\u9001\u4fe1\u3057\u307e\u3059\u3002<a href=\"https:\/\/www.twilio.com\/docs\/sendgrid\/for-developers\/sending-email\/enforced-tls\" rel=\"noopener\" target=\"_blank\">\u5f37\u5236TLS<\/a>\u3067\u306f\u3001\u5b9b\u5148\u30b5\u30fc\u30d0\u304c\u6697\u53f7\u5316\u901a\u4fe1\u3092\u53d7\u3051\u4ed8\u3051\u306a\u3044\u5834\u5408\u306f\u30e1\u30c3\u30bb\u30fc\u30b8\u306f\u7834\u68c4\u3055\u308c\u3001Block\u30a4\u30d9\u30f3\u30c8\u304c\u767a\u751f\u3057\u307e\u3059\u3002<\/p>\n<p>\u304a\u5ba2\u69d8\u304cSTARTTLS\u3092\u4f7f\u7528\u3059\u308b\u306e\u306f\u3001\u4e3b\u306bSendGrid\u306b\u5bfe\u3057\u3066SMTP\u63a5\u7d9a\u3092\u884c\u3046\u30bf\u30a4\u30df\u30f3\u30b0\u3067\u3059\u3002SendGrid\u304b\u3089\u5b9b\u5148\u30b5\u30fc\u30d0\u3078\u306e\u9001\u4fe1\u6642\u306b\u304a\u3051\u308b\u3001TLS\u8a3c\u660e\u66f8\u306e\u691c\u8a3c\u3084\u6697\u53f7\u5316\u30d7\u30ed\u30bb\u30b9\u3001\u305d\u306e\u4ed6\u306e\u554f\u984c\u306e\u51e6\u7406\u306f\u3001SendGrid\u304c\u884c\u3044\u307e\u3059\u3002<\/p>\n<p>SendGrid\u304a\u3088\u3073SMTP\u306e\u8a73\u7d30\u306b\u3064\u3044\u3066\u306f\u3001\u30c9\u30ad\u30e5\u30e1\u30f3\u30c8\u300c<a href=\"https:\/\/sendgrid.kke.co.jp\/docs\/API_Reference\/SMTP_API\/getting_started_smtp.html\" rel=\"noopener\" target=\"_blank\">SMTP\u3067\u30e1\u30fc\u30eb\u9001\u4fe1\u3059\u308b<\/a>\u300d\u3092\u3054\u89a7\u304f\u3060\u3055\u3044\u3002<\/p>\n<h3>\u3088\u304f\u3042\u308b\u8cea\u554f<\/h3>\n<p><strong>Q\uff1aSTARTTLS\u306f\u3069\u306e\u30dd\u30fc\u30c8\u3092\u4f7f\u7528\u3057\u307e\u3059\u304b\uff1f<\/strong><\/p>\n<p>STARTTLS\u3067\u306f\u901a\u5e38587\u756a\u30dd\u30fc\u30c8\u3092\u4f7f\u7528\u3057\u307e\u3059\u3002\u3053\u308c\u306f\u6697\u53f7\u5316\u3055\u308c\u305f\u30e1\u30fc\u30eb\u9001\u4fe1\u306b\u304a\u3051\u308b\u6a19\u6e96\u7684\u306a\u30dd\u30fc\u30c8\u3067\u3059\u300225\u756a\u30012525\u756a\u3082STARTTLS\u306b\u5bfe\u5fdc\u3057\u3066\u3044\u307e\u3059\u304c\u3001\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3067\u306f587\u756a\u3092\u4f7f\u7528\u3059\u308b\u3053\u3068\u304c\u63a8\u5968\u3055\u308c\u307e\u3059\u3002<\/p>\n<p><strong>Q\uff1aSTARTTLS\u306f\u5b89\u5168\u3067\u3059\u304b\uff1f<\/strong><\/p>\n<p>STARTTLS\u306f\u3001\u9069\u5207\u306b\u8a2d\u5b9a\u3055\u308c\u3066\u3044\u308c\u3070\u5f37\u56fa\u306a\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u3092\u63d0\u4f9b\u3057\u307e\u3059\u304c\u3001\u30ea\u30b9\u30af\u304c\u306a\u3044\u308f\u3051\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002\u901a\u4fe1\u958b\u59cb\u76f4\u5f8c\u306e\u6697\u53f7\u5316\u3055\u308c\u3066\u3044\u306a\u3044\u30cf\u30f3\u30c9\u30b7\u30a7\u30a4\u30af\u306e\u6bb5\u968e\u3067\u306f\u3001\u4e2d\u9593\u8005\u653b\u6483\u3092\u53d7\u3051\u308b\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002\u6700\u5927\u9650\u306e\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u3092\u78ba\u4fdd\u3059\u308b\u306b\u306f\u3001\u8a3c\u660e\u66f8\u306e\u691c\u8a3c\u3092\u6709\u52b9\u306b\u3057\u305fSTARTTLS\u3092\u4f7f\u7528\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n<p><strong>Q\uff1a\u3069\u3046\u3059\u308c\u3070STARTTLS\u3092\u6709\u52b9\u306b\u3067\u304d\u307e\u3059\u304b\uff1f<\/strong><\/p>\n<p>\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u306eSMTP\u8a2d\u5b9a\u3067STARTTLS\u3092\u6709\u52b9\u306b\u3057\u3066\u304f\u3060\u3055\u3044\u3002\u4f8b\u3048\u3070\u300cSTARTTLS\u3092\u4f7f\u7528\u3059\u308b\u300d\u3001\u300c\u660e\u793a\u7684TLS\u300d\u3001\u300cTLS\/STARTTLS\u300d\u3068\u3044\u3063\u305f\u9805\u76ee\u3092\u9078\u629e\u3057\u307e\u3059\uff08\u300cSSL\u300d\u3084\u300c\u6697\u9ed9\u7684TLS\u300d\u3067\u306f\u3042\u308a\u307e\u305b\u3093\uff09\u3002<\/p>\n<p><strong>Q\uff1aSTARTTLS\u3068SSL\u306e\u9055\u3044\u306f\u4f55\u3067\u3059\u304b\uff1f<\/strong><\/p>\n<p>STARTTLS\u306f\u65e2\u5b58\u306e\u63a5\u7d9a\u3092\u6697\u53f7\u5316\u901a\u4fe1\u306b\u5207\u308a\u66ff\u3048\u308b\u306e\u306b\u5bfe\u3057\u3001SSL\u306f\u521d\u3081\u304b\u3089\u6697\u53f7\u5316\u63a5\u7d9a\u3092\u884c\u3044\u307e\u3059\u3002STARTTLS\u306f1\u3064\u306e\u30dd\u30fc\u30c8\u3067\u6697\u53f7\u5316\u901a\u4fe1\u3068\u975e\u6697\u53f7\u5316\u901a\u4fe1\u306e\u4e21\u65b9\u306b\u5bfe\u5fdc\u3067\u304d\u308b\u305f\u3081\u3001\u3088\u308a\u67d4\u8edf\u6027\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n<p><strong>Q\uff1a\u300cStartTLS is 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What is StartTLS? \u306e\u6284\u8a33\u3067\u3059\u3002 \u30e1\u30fc\u30eb\u304c\u30b5\u30fc\u30d0\u304b\u3089\u30b5\u30fc\u30d0\u3078\u3068\u3069\u306e\u3088\u3046\u306b\u5b89\u5168\u306b\u9001\u4fe1\u3055\u308c\u308b\u306e\u304b\u3001\u7591\u554f\u306b\u601d\u3063\u305f\u3053\u3068\u306f\u3042\u308a\u307e\u305b\u3093\u304b\uff1f \u30e1\u30fc\u30eb\u9001\u4fe1\u7528\u306e\u30d7\u30ed\u30c8\u30b3\u30eb\u3067\u3042\u308bSMTP\u3067\u306f\u3001STARTTLS\u306b\u3088 <a class=\"read-more\" href=\"https:\/\/sendgrid.kke.co.jp\/blog\/?p=12756\">&#8230;\u7d9a\u304d\u3092\u8aad\u3080<\/a><\/p>\n","protected":false},"author":2,"featured_media":20783,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[11],"tags":[],"class_list":["post-12756","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-technical"],"acf":[],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/sendgrid.kke.co.jp\/blog\/index.php?rest_route=\/wp\/v2\/posts\/12756","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sendgrid.kke.co.jp\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/sendgrid.kke.co.jp\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/sendgrid.kke.co.jp\/blog\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/sendgrid.kke.co.jp\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=12756"}],"version-history":[{"count":8,"href":"https:\/\/sendgrid.kke.co.jp\/blog\/index.php?rest_route=\/wp\/v2\/posts\/12756\/revisions"}],"predecessor-version":[{"id":20788,"href":"https:\/\/sendgrid.kke.co.jp\/blog\/index.php?rest_route=\/wp\/v2\/posts\/12756\/revisions\/20788"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/sendgrid.kke.co.jp\/blog\/index.php?rest_route=\/wp\/v2\/media\/20783"}],"wp:attachment":[{"href":"https:\/\/sendgrid.kke.co.jp\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=12756"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/sendgrid.kke.co.jp\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=12756"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/sendgrid.kke.co.jp\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=12756"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}