{"id":135,"date":"2026-10-10T17:01:18","date_gmt":"2026-10-10T14:01:18","guid":{"rendered":"https:\/\/mx1mail.com\/blog\/smtp-relay-nedir-smtp-submission-farklari-dogru-kullanim-guvenli-yapilandirma\/"},"modified":"2026-10-10T17:01:18","modified_gmt":"2026-10-10T14:01:18","slug":"smtp-relay-nedir-smtp-submission-farklari-dogru-kullanim-guvenli-yapilandirma","status":"publish","type":"post","link":"https:\/\/mx1mail.com\/blog\/tr\/smtp-relay-nedir-smtp-submission-farklari-dogru-kullanim-guvenli-yapilandirma\/","title":{"rendered":"SMTP Relay Nedir? SMTP Submission ile Farklar\u0131, Do\u011fru Kullan\u0131m Senaryolar\u0131 ve G\u00fcvenli Yap\u0131land\u0131rma"},"content":{"rendered":"<h2>SMTP relay ve SMTP submission neden kar\u0131\u015ft\u0131r\u0131l\u0131r?<\/h2>\n<p>\u015eirketlerde \u201cmail g\u00f6nderimi\u201d tek bir i\u015flem gibi g\u00f6r\u00fcnse de altyap\u0131 taraf\u0131nda iki farkl\u0131 kullan\u0131m modeli vard\u0131r: kullan\u0131c\u0131lar\u0131n e-posta istemcisiyle yapt\u0131\u011f\u0131 g\u00f6nderim (SMTP submission) ve bir sistemin ba\u015fka bir sisteme e-posta aktarmas\u0131 (SMTP relay). Bu iki kavram g\u00fcnl\u00fck dilde \u00e7o\u011fu zaman \u201cSMTP\u201d diye tek kelimeyle ifade edildi\u011fi i\u00e7in kar\u0131\u015f\u0131r. Oysa do\u011fru se\u00e7ilmedi\u011finde g\u00fcvenlik a\u00e7\u0131klar\u0131, spam riski, eri\u015fim sorunlar\u0131 ve teslim edilebilirlik problemleri olu\u015fabilir.<\/p>\n<p>Bu yaz\u0131da SMTP relay\u2019in ne oldu\u011funu, SMTP submission\u2019dan farklar\u0131n\u0131, yayg\u0131n senaryolar\u0131 ve i\u015fletmeler i\u00e7in g\u00fcvenli yap\u0131land\u0131rma prensiplerini ele al\u0131yoruz. Ama\u00e7, hem IT ekiplerinin hem de teknik karar vericilerin \u201changi g\u00f6nderim t\u00fcr\u00fcn\u00fc nerede kullanmal\u0131y\u0131m?\u201d sorusuna net cevap almas\u0131d\u0131r.<\/p>\n<h2>Temel kavramlar: MUA, MSA, MTA nedir?<\/h2>\n<p>Kavramlar\u0131 oturtmak, do\u011fru tasar\u0131m\u0131 kolayla\u015ft\u0131r\u0131r. E-posta g\u00f6nderim yolculu\u011funda genellikle \u00fc\u00e7 rol \u00f6ne \u00e7\u0131kar:<\/p>\n<ul>\n<li><strong>MUA (Mail User Agent)<\/strong>: Outlook, Apple Mail, mobil uygulamalar gibi kullan\u0131c\u0131 istemcileri.<\/li>\n<li><strong>MSA (Mail Submission Agent)<\/strong>: Kullan\u0131c\u0131dan e-postay\u0131 \u201ckabul eden\u201d ve kimlik do\u011frulayan katman. Genellikle submission portlar\u0131 \u00fczerinden \u00e7al\u0131\u015f\u0131r.<\/li>\n<li><strong>MTA (Mail Transfer Agent)<\/strong>: E-postay\u0131 sunucudan sunucuya aktaran transfer katman\u0131. Relay kavram\u0131 daha \u00e7ok bu seviyededir.<\/li>\n<\/ul>\n<p>Pratikte ayn\u0131 mail sunucusu hem MSA hem MTA g\u00f6revini \u00fcstlenebilir. \u00d6nemli olan, hangi port ve hangi kuralla hangi trafi\u011fin kabul edildi\u011fidir.<\/p>\n<h2>SMTP submission nedir?<\/h2>\n<p><strong>SMTP submission<\/strong>, kullan\u0131c\u0131lar\u0131n veya kullan\u0131c\u0131 ad\u0131na \u00e7al\u0131\u015fan istemcilerin (\u00f6r. telefon, e-posta uygulamas\u0131) e-posta g\u00f6ndermek i\u00e7in mail sunucusuna ba\u011fland\u0131\u011f\u0131 y\u00f6ntemdir. Buradaki kritik nokta, submission trafi\u011finin \u201cg\u00f6nderim niyetiyle\u201d geldi\u011finin varsay\u0131lmas\u0131 ve bu nedenle kimlik do\u011frulama ile politika kontrollerinin s\u0131k\u0131 uygulanmas\u0131d\u0131r.<\/p>\n<p>Submission genellikle \u015fu \u00f6zelliklerle tan\u0131mlan\u0131r:<\/p>\n<ul>\n<li>Kimlik do\u011frulama (SMTP AUTH) beklenir.<\/li>\n<li>TLS ile \u015fifreleme zorlan\u0131r ya da g\u00fc\u00e7l\u00fc bi\u00e7imde te\u015fvik edilir.<\/li>\n<li>G\u00f6nderen adresi, kullan\u0131c\u0131\/hesap yetkileriyle ili\u015fkilendirilebilir (policy enforcement).<\/li>\n<li>Kullan\u0131c\u0131 bazl\u0131 kota, h\u0131z limiti, anomali tespiti gibi kontroller uygulanabilir.<\/li>\n<\/ul>\n<p>\u00d6zetle submission, \u201ckullan\u0131c\u0131dan sunucuya\u201d g\u00fcvenli g\u00f6nderim kap\u0131s\u0131d\u0131r.<\/p>\n<h2>SMTP relay nedir?<\/h2>\n<p><strong>SMTP relay<\/strong>, bir mail sunucusunun ba\u015fka bir mail sunucusuna e-posta iletmesidir. Bu, internet \u00fczerindeki standart e-posta ak\u0131\u015f\u0131n\u0131n do\u011fal par\u00e7as\u0131d\u0131r. Ayr\u0131ca \u015firket i\u00e7inde uygulamalar, yaz\u0131c\u0131lar, CRM sistemleri veya ba\u015fka sunucular da bir \u201crelay\u201d \u00fczerinden e-posta g\u00f6nderebilir.<\/p>\n<p>Relay\u2019in tipik \u00f6zellikleri \u015funlard\u0131r:<\/p>\n<ul>\n<li>Kimlik do\u011frulama her zaman zorunlu de\u011fildir; bunun yerine IP bazl\u0131 yetkilendirme veya a\u011f segmenti k\u0131s\u0131tlar\u0131 kullan\u0131labilir.<\/li>\n<li>Sunucudan sunucuya teslimatta TLS kullan\u0131labilir, ancak her zaman garanti de\u011fildir; bu nedenle ek politikalar gerekebilir.<\/li>\n<li>Yanl\u0131\u015f yap\u0131land\u0131r\u0131l\u0131rsa \u201copen relay\u201d riskine yol a\u00e7abilir ve spam kaynakl\u0131 ciddi itibar kayb\u0131 ya\u015fanabilir.<\/li>\n<\/ul>\n<p>Relay, \u201csunucudan sunucuya\u201d ta\u015f\u0131ma hatt\u0131d\u0131r; g\u00fcvenlik ve yetkilendirme modeli submission\u2019dan farkl\u0131 d\u00fc\u015f\u00fcn\u00fclmelidir.<\/p>\n<h2>SMTP relay ve submission aras\u0131ndaki kritik farklar<\/h2>\n<h3>1) Kimlik do\u011frulama ve yetkilendirme modeli<\/h3>\n<p>Submission\u2019da kimlik do\u011frulama neredeyse standartt\u0131r. Relay\u2019de ise \u00e7o\u011fu tasar\u0131m, belirli IP\u2019lerin ya da a\u011flar\u0131n relay yapmas\u0131na izin verir. Uygulama sunucular\u0131 (web app, ERP) \u00e7o\u011fu zaman kullan\u0131c\u0131 ad\u0131\/parola yerine IP allowlist ile \u00e7al\u0131\u015ft\u0131r\u0131l\u0131r. Burada \u201cen kolay\u201d yakla\u015f\u0131m \u00e7o\u011fu zaman \u201cen riskli\u201d yakla\u015f\u0131ma d\u00f6n\u00fc\u015febilir; IP allowlist kullan\u0131l\u0131yorsa a\u011f izolasyonu, g\u00fcvenlik duvar\u0131 ve log izleme \u00f6nem kazan\u0131r.<\/p>\n<h3>2) Portlar ve trafik t\u00fcr\u00fc<\/h3>\n<p>Submission trafi\u011fi \u00e7o\u011fu ortamda ayr\u0131 portlarda tutulur. B\u00f6ylece kullan\u0131c\u0131 trafi\u011fi ile sunucudan sunucuya relay trafi\u011fi ayr\u0131\u015f\u0131r; politika ve g\u00fcvenlik kontrolleri daha net uygulan\u0131r. Relay trafi\u011fi ise \u00e7o\u011fu zaman standart SMTP transfer portu \u00fczerinden ger\u00e7ekle\u015fir. Bu ayr\u0131m, sorun giderirken de b\u00fcy\u00fck kolayl\u0131k sa\u011flar: \u201cKullan\u0131c\u0131 g\u00f6nderemiyor\u201d ile \u201csunucular aras\u0131 iletimde sorun var\u201d farkl\u0131 te\u015fhis s\u00fcre\u00e7leri gerektirir.<\/p>\n<h3>3) Teslim edilebilirlik (deliverability) etkisi<\/h3>\n<p>Submission taraf\u0131nda hatal\u0131 kimlik bilgileri, k\u00f6t\u00fc ama\u00e7l\u0131 oturum a\u00e7ma denemeleri veya ele ge\u00e7irilmi\u015f hesaplar, k\u0131sa s\u00fcrede y\u00fcksek hacimli spam \u00e7\u0131k\u0131\u015f\u0131na neden olabilir. Relay taraf\u0131nda ise open relay veya yanl\u0131\u015f yetkilendirme, d\u0131\u015far\u0131ya kontrols\u00fcz spam ak\u0131tabilir. Her iki durum da IP ve domain itibar\u0131n\u0131 zedeleyerek me\u015fru e-postalar\u0131n spam klas\u00f6r\u00fcne d\u00fc\u015fmesine yol a\u00e7abilir.<\/p>\n<h3>4) G\u00fcnl\u00fckleme (logging) ve izlenebilirlik<\/h3>\n<p>Submission\u2019da \u201changi kullan\u0131c\u0131 hangi cihazdan ne g\u00f6nderdi?\u201d sorusuna cevap \u00fcretmek daha kolayd\u0131r. Relay senaryolar\u0131nda ise kayna\u011f\u0131 do\u011fru etiketlemek i\u00e7in uygulama bazl\u0131 header ekleme, ayr\u0131 outbound IP kullan\u0131m\u0131 veya sistem hesab\u0131 bazl\u0131 kimlik do\u011frulama gibi y\u00f6ntemler gerekebilir.<\/p>\n<h2>Hangi senaryoda hangisini kullanmal\u0131s\u0131n\u0131z?<\/h2>\n<h3>Kullan\u0131c\u0131lar (Outlook, telefon, masa\u00fcst\u00fc istemcisi)<\/h3>\n<p>Kural nettir: Kullan\u0131c\u0131 istemcileri i\u00e7in submission kullan\u0131n. \u00c7\u00fcnk\u00fc kimlik do\u011frulama, TLS ve kullan\u0131c\u0131 politikalar\u0131 bu model i\u00e7in tasarlanm\u0131\u015ft\u0131r. Kullan\u0131c\u0131n\u0131n evden, otelden veya mobil a\u011fdan ba\u011fland\u0131\u011f\u0131 d\u00fc\u015f\u00fcn\u00fcl\u00fcrse IP bazl\u0131 relay zaten pratik de\u011fildir.<\/p>\n<h3>Web sitesi ileti\u015fim formlar\u0131 ve uygulamalar<\/h3>\n<p>Uygulamalar iki \u015fekilde e-posta g\u00f6nderir: ya submission ile bir servis hesab\u0131 kullan\u0131r ya da a\u011f i\u00e7inde bir relay noktas\u0131na ba\u011flan\u0131r. G\u00fcvenlik a\u00e7\u0131s\u0131ndan genellikle tercih edilen yakla\u015f\u0131m, uygulamaya \u00f6zel bir hesapla kimlik do\u011frulamal\u0131 g\u00f6nderim yapmakt\u0131r. IP allowlist ile relay yap\u0131lacaksa yaln\u0131zca gerekli sunuculara izin verilmesi, a\u011f segmentinin izole edilmesi ve rate limit uygulanmas\u0131 gerekir.<\/p>\n<h3>Yaz\u0131c\u0131lar, taray\u0131c\u0131lar, IoT cihazlar\u0131<\/h3>\n<p>Bu cihazlar bazen modern TLS\/kimlik do\u011frulama \u00f6zelliklerini desteklemez. Bu durumda \u015firket i\u00e7i a\u011fda k\u0131s\u0131tl\u0131 bir relay noktas\u0131 olu\u015fturulabilir. Ancak bu relay, internete a\u00e7\u0131k \u201cherkese\u201d hizmet vermemeli; sadece belirli IP\u2019lerden gelen trafi\u011fi kabul etmeli ve m\u00fcmk\u00fcnse sadece \u015firket alan adlar\u0131 i\u00e7in g\u00f6nderime izin vermelidir.<\/p>\n<h3>Sunucudan sunucuya e-posta aktar\u0131m\u0131<\/h3>\n<p>\u0130nternet \u00fczerindeki normal e-posta ak\u0131\u015f\u0131 relay mant\u0131\u011f\u0131yla \u00e7al\u0131\u015f\u0131r. Burada temel hedef, do\u011fru DNS ve kimlik do\u011frulama temeli (SPF\/DKIM\/DMARC) ile tutarl\u0131 bir \u00e7\u0131k\u0131\u015f politikas\u0131 olu\u015fturmakt\u0131r. Ayr\u0131ca TLS politikalar\u0131, kuyruk y\u00f6netimi ve geri d\u00f6n\u00fc\u015f kodlar\u0131n\u0131n izlenmesi operasyonel kaliteyi belirler.<\/p>\n<h2>G\u00fcvenli yap\u0131land\u0131rma i\u00e7in pratik kontrol listesi<\/h2>\n<h3>Open relay riskini s\u0131f\u0131rlay\u0131n<\/h3>\n<p>Relay yap\u0131land\u0131rmas\u0131nda en b\u00fcy\u00fck risk, yetkisiz kaynaklar\u0131n sunucunuzu kullanarak d\u0131\u015far\u0131ya e-posta g\u00f6nderebilmesidir. Bu, \u00e7ok k\u0131sa s\u00fcrede kara listeye girmeye kadar uzanabilir. G\u00fcvenli yakla\u015f\u0131m:<\/p>\n<ul>\n<li>Relay iznini yaln\u0131zca belirli IP\u2019lerle veya kimli\u011fi do\u011frulanm\u0131\u015f hesaplarla s\u0131n\u0131rland\u0131r\u0131n.<\/li>\n<li>\u0130\u00e7 a\u011fdan bile gelse, g\u00f6nderim alan adlar\u0131n\u0131 ve al\u0131c\u0131 kapsam\u0131n\u0131 politika ile s\u0131n\u0131rlamay\u0131 de\u011ferlendirin.<\/li>\n<li>Gereksiz portlar\u0131 kapat\u0131n, g\u00fcvenlik duvar\u0131nda kaynak\/destinasyon k\u0131s\u0131tlar\u0131 tan\u0131mlay\u0131n.<\/li>\n<\/ul>\n<h3>TLS kullan\u0131m\u0131n\u0131 standartla\u015ft\u0131r\u0131n<\/h3>\n<p>Submission taraf\u0131nda TLS\u2019i m\u00fcmk\u00fcn oldu\u011funca zorunlu k\u0131l\u0131n. Relay taraf\u0131nda ise \u201cher zaman TLS olur\u201d varsay\u0131m\u0131 ger\u00e7ek\u00e7i olmayabilir; bu nedenle TLS\u2019i te\u015fvik eden ve raporlanabilir k\u0131lan bir yakla\u015f\u0131m tercih edilir. Hangi taraf\u0131n hangi d\u00fczeyde TLS sa\u011flad\u0131\u011f\u0131n\u0131 bilmek, risk y\u00f6netimi a\u00e7\u0131s\u0131ndan \u00f6nemlidir.<\/p>\n<h3>Rate limit ve anomali kontrolleri uygulay\u0131n<\/h3>\n<p>Ele ge\u00e7irilmi\u015f bir hesap veya hatal\u0131 yap\u0131land\u0131r\u0131lm\u0131\u015f bir uygulama, dakikalar i\u00e7inde binlerce e-posta g\u00f6nderebilir. G\u00f6nderim h\u0131z limiti, e\u015fik uyar\u0131lar\u0131 ve karantina benzeri kontroller; hem itibar\u0131n\u0131z\u0131 hem de operasyonel s\u00fcreklili\u011fi korur.<\/p>\n<h3>G\u00f6nderen adresi kontrol\u00fc yap\u0131n<\/h3>\n<p>Submission\u2019da, kullan\u0131c\u0131n\u0131n \u201cFrom\u201d alan\u0131nda farkl\u0131 bir alan ad\u0131 kullanmas\u0131n\u0131 engellemek ya da en az\u0131ndan izlemek iyi bir pratiktir. Relay\u2019de de uygulama veya cihazlar\u0131n, beklenmedik g\u00f6nderen adresleriyle mail \u00e7\u0131karmas\u0131n\u0131 \u00f6nleyecek kurallar planlanmal\u0131d\u0131r. Bu, DMARC uyumu ve marka b\u00fct\u00fcnl\u00fc\u011f\u00fc a\u00e7\u0131s\u0131ndan da faydal\u0131d\u0131r.<\/p>\n<h3>Loglar\u0131 anlaml\u0131 hale getirin<\/h3>\n<p>Sorun oldu\u011funda h\u0131zl\u0131 te\u015fhis i\u00e7in loglar\u0131n i\u015fe yarar olmas\u0131 gerekir. \u00d6neriler:<\/p>\n<ul>\n<li>Uygulama kaynaklar\u0131n\u0131 ayr\u0131 IP, ayr\u0131 kimlik veya ayr\u0131 etiketlerle ayr\u0131\u015ft\u0131r\u0131n.<\/li>\n<li>G\u00f6nderim hatalar\u0131n\u0131 (bounce) d\u00fczenli inceleyin ve tekrarlayan nedenleri giderin.<\/li>\n<li>Kimlik do\u011frulama hatalar\u0131n\u0131 ve ba\u015far\u0131s\u0131z oturum a\u00e7ma denemelerini izleyin.<\/li>\n<\/ul>\n<h2>Yanl\u0131\u015f se\u00e7imlerin tipik sonu\u00e7lar\u0131<\/h2>\n<h3>\u201cCihaz relay yaps\u0131n\u201d deyip internetten a\u00e7\u0131k b\u0131rakmak<\/h3>\n<p>En s\u0131k g\u00f6r\u00fclen hatalardan biridir. Bir yaz\u0131c\u0131 veya uygulama e-posta g\u00f6ndersin diye relay a\u00e7\u0131l\u0131r, sonra bu servis internete a\u00e7\u0131k kal\u0131r. Sonu\u00e7: istenmeyen g\u00f6nderimler, itibar kayb\u0131 ve teslim edilebilirlik sorunlar\u0131.<\/p>\n<h3>Kullan\u0131c\u0131lar\u0131 relay \u00fczerinden g\u00f6ndermeye zorlamak<\/h3>\n<p>Baz\u0131 ortamlarda kullan\u0131c\u0131lar 25 benzeri transfer mant\u0131\u011f\u0131yla g\u00f6ndermeye \u00e7al\u0131\u015ft\u0131r\u0131l\u0131r. Bu, kimlik do\u011frulama, dola\u015f\u0131m kullan\u0131c\u0131lar\u0131 ve g\u00fcvenlik politikalar\u0131 a\u00e7\u0131s\u0131ndan sorun \u00e7\u0131kar\u0131r. Kullan\u0131c\u0131lar i\u00e7in do\u011fru model submission\u2019d\u0131r.<\/p>\n<h2>Sonu\u00e7: do\u011fru ak\u0131\u015f\u0131 se\u00e7mek, hem g\u00fcvenli\u011fi hem teslimat\u0131 iyile\u015ftirir<\/h2>\n<p>SMTP submission, kullan\u0131c\u0131 g\u00f6nderimi i\u00e7in kimlik do\u011frulamal\u0131 ve politika kontroll\u00fc bir kap\u0131d\u0131r. SMTP relay ise sunucudan sunucuya aktar\u0131m\u0131n ve baz\u0131 sistem entegrasyonlar\u0131n\u0131n temelidir. \u0130kisini do\u011fru ay\u0131rmak; open relay riskini azalt\u0131r, izlenebilirli\u011fi art\u0131r\u0131r ve teslim edilebilirlik dalgalanmalar\u0131n\u0131 \u00f6nlemeye yard\u0131mc\u0131 olur.<\/p>\n<p>MX1Mail gibi kurumsal e-posta altyap\u0131lar\u0131nda da g\u00f6nderim ak\u0131\u015flar\u0131n\u0131 planlarken kullan\u0131c\u0131 g\u00f6nderimi (submission) ile sistem\/entegrasyon trafi\u011fini (relay) ayr\u0131 d\u00fc\u015f\u00fcnmek; port, yetkilendirme, TLS ve loglama kararlar\u0131n\u0131 daha tutarl\u0131 hale getirir. Mevcut kurulumunuzu de\u011ferlendirirken ilk ad\u0131m, hangi kaynaklar\u0131n hangi y\u00f6ntemle mail g\u00f6nderdi\u011fini envanterlemek ve her birini uygun modele ta\u015f\u0131makt\u0131r.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>SMTP relay ve SMTP submission aras\u0131ndaki farklar\u0131, hangi senaryoda hangisinin kullan\u0131laca\u011f\u0131n\u0131 ve \u015firketlerde g\u00fcvenli e-posta g\u00f6nderimi i\u00e7in do\u011fru yap\u0131land\u0131rma ad\u0131mlar\u0131n\u0131 \u00f6\u011frenin.<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[211],"tags":[114,226,277],"class_list":["post-135","post","type-post","status-publish","format-standard","hentry","category-e-posta-altyapisi","tag-e-posta-guvenligi","tag-smtp","tag-teslim-edilebilirlik"],"_links":{"self":[{"href":"https:\/\/mx1mail.com\/blog\/wp-json\/wp\/v2\/posts\/135","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mx1mail.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mx1mail.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mx1mail.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mx1mail.com\/blog\/wp-json\/wp\/v2\/comments?post=135"}],"version-history":[{"count":0,"href":"https:\/\/mx1mail.com\/blog\/wp-json\/wp\/v2\/posts\/135\/revisions"}],"wp:attachment":[{"href":"https:\/\/mx1mail.com\/blog\/wp-json\/wp\/v2\/media?parent=135"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mx1mail.com\/blog\/wp-json\/wp\/v2\/categories?post=135"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mx1mail.com\/blog\/wp-json\/wp\/v2\/tags?post=135"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}