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The TCP/IP Guide  9  TCP/IP Application Layer Protocols, Services and Applications (OSI Layers 5, 6 and 7)       9  TCP/IP Key Applications and Application Protocols            9  TCP/IP File and Message Transfer Applications and Protocols (FTP, TFTP, Electronic Mail, USENET, HTTP/WWW, Gopher)                 9  TCP/IP Electronic Mail System: Concepts and Protocols (RFC 822, MIME, SMTP, POP3, IMAP)

TCP/IP Electronic Mail System: Concepts and Protocols (RFC 822, MIME, SMTP, POP3, IMAP) 1 TCP/IP Electronic Mail System Overview and History

Electronic mail in the TCP/IP protocol suite is not implemented as just a single protocol or technology. Rather, it is a complete system that contains a number of related components that work together. These include standards defining methods for addressing and message formatting, and a number of protocols that play different functions in implementing electronic mail messaging. Before proceeding to examine each of these pieces, it makes sense to start with an overview of the system as a whole.

In this section I provide an introductory look at TCP/IP electronic mail, to help you understand the system, how it works, and how different components fit into it. I begin with an overview and history of e-mail and its implementation in TCP/IP. I provide a general overview of the steps involved in the e-mail communication process. I conclude with a more specific discussion of the communication model used in TCP/IP and the roles played by various TCP/IP devices and protocols in the sending and receiving of electronic mail.

TCP/IP Electronic Mail System: Concepts and Protocols (RFC 822, MIME, SMTP, POP3, IMAP) 1 TCP/IP Electronic Mail System Overview and History