电子邮件中发送域是什么?
IP主机名(IP hostname)
发件人信封域(Envelope sender domain)
发送域(From header domain)
回复域(Reply-To header domain)
发件人域(Sender header domain)
消息ID域(Message-ID header domain)
DKIM签名域(DKIM signing domain)
图片URI域(Image URI domain)
链接URI域(Link URI domain)
