DOS 下发送邮件（国外英文资料）.doc

DOS 下发送邮件（国外英文资料） DOS to send mail (2010-01-07 10:27:27:16) using the SMTP command Reprinting label: it classification: it Simple Mail Transfer Protocol: An E-mail is transmitted from the client to the server (send mail) or transfer protocol from one server to another. SMTP is the request/response protocol, which is based on ASCII text and ends with the CR and LF. The response includes a three-digit code that represents the return state (and the pop is the corresponding + OK and -err). SMTP listens for connection requests on TCPs 25 port. As the name implies, extending SMTP is an extension of the standard SMTP protocol. The difference between it and the SMTP service is only, use SMTP mail does not need to validate user account, and use ESMTP transmitting, the server will require the user to provide a user name and password to authenticate. The mail sending process after validation is no different from SMTP. B. connection and sending process: A. establish a TCP connection (for example, Telnet or Socket) B. the client sends HELO (or EHLO authentication is required) command to identify the senders own identity, and then the client sends the MAIL server correct hope OK as responses FROM command, that is ready to receive C. The client sends the RCPT TO command TO identify the intended recipient of the E-mail, and multiple RCPT servers will be able TO indicate whether they are willing TO receive mail for the recipient D. negotiate over, send mail, send with command DATA (a single line) indicates that the input content is sent out together End this sending, QUIT with QUIT command. The email routing process: The SMTP server is based on the name of the domain name service DNS and the recipients domain name is routed by E-mail. SMTP server based on DNS MX records in the background by E-mail, MX records registered domain names and related SMTP relay main   charm sweat mi fly negundo Qian on beginning  plus western gnats roll  once dean? / P If SMTP server receives a lett