SMTP
:25
Simple Mail Transfer Protocol
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Application Layer — Email
协议概览
全称
Simple Mail Transfer Protocol
缩写
SMTP
OSI 层
Application Layer
类别
Email
默认端口
25, 465, 587
RFC
RFC 5321
关于 SMTP
Standard protocol for sending email between mail servers. Handles message routing, delivery, and relay across the internet.
Application Layer
Email
端口 25, 465, 587
标准参考
SMTP定义于互联网工程任务组（IETF）发布的RFC 5321中。RFC是互联网协议的官方标准文档，可免费公开查阅。