In this, I ll show a simple implementation of Simple Mail Transfer Protocol (SMTP) that is defined in RFC 821. According to the document - The objective of Simple Mail Transfer Protocol (SMTP) is to transfer mail reliably and efficiently. SMTP is independent of the particular transmission subsystem and requires only a reliable ordered data stream channel. In this article, we use TCP/IP only for message distribution.-In this, I ll show a simple implementation of Simple Mail Transfer Protocol (SMTP) that is defined in RFC 821. According to the document- The objective of Simple Mail Transfer Protocol (SMTP) is to transfer mail reliably and efficiently. SMTP is independent of the particular transmission subsystem and requires only a reliable ordered data stream channel. In this article, we use TCP/IP only for message distribution.