page 287 provides an overview of the ClientAccess-based POP server
components.
All incoming mail from SMTP for local users (users with mail accounts on this
AS/400) is processed by the AnyMail/400 framework. The mail server framework is
a mail distribution structure that allows the distribution of E-mail. The mail server
framework calls exit programs or snap-ins to handle specific mail types.
For the client/server interface to work, SMTP must be running for the following
reasons:
vBoth Internet mail and mail that is sent to clients on the same system go through
SMTP.
vAny mail that goes through the mail server framework needs to go through SMTP
(through a snap-in) to be delivered to external users.
The POP server serves as a temporary holding area for mail until it is retrieved by
the mail client — it does not provide a “mail store” function. When the mail client
connects to the server, it queries the contents of its mailbox to see if there is any
mail to retrieve. If there is, it retrieves the mail one message at a time. Once a
message has been retrieved, the client normally instructs the server to mark that
message for deletion when the client session is complete. The client retrieves all of
Figure 184. Overview of POPServer Components. Shows “standard” POP clients such as
Netscape** and Eudora**.
286 OS/400 TCP/IPConfiguration and Reference V4R4