The mail world - Mail servers, spam control and virus scanners

The mail world - Mail servers, spam control and virus scanners

Introduction to SMTP SMTP stands for simple mail transfer protocol and is documented in RFC5321 but it has been standardized some 30 years ago stared long long ago. Such a long time ago when Internet was just in its infancy and email was still being considered a hobby project. It is a text based project a la HTTP and it has only 5 or so commands. HELO/EHLO MAIL FROM RCPT TO DATA QUIT And the status codes also match the standard HTTP codes in what it means to have a 2xx or 4xx response.

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