... are affirmative, information about the message is passed, and requests to pass the message are made> The destination server then gives permission and the message is passed, verified and contact is terminated Figure displaying SMTP model SMTP is basically based on an end-to-end delivery, so the connection from SMTP client to SMTP server is a direct connection. Using a mail gateway for sending mail, SMTP cant route directly to the recipients host, so a different approach is taken which is where SMTP sends the mail from; host to gateway, gateway to gateway, gateway to host. This basically means that for mail transmission beyond the TCP/IP network to the destination host, SMTP is not defined. The DNS information within the java application using SMTP is organised into lines of information called resource records (RR), each having different meanings and purposes. The MX (Mail eXchanger) is what records the name and prioritises the mail servers ...

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