PLANET CS-2000 User Manual
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CS-2000 UTM Content Security Gateway User’s Manual
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Mail Transferring Process:
The 3 elements of the e-mail send / retrieve:MUA, MTA, MDA.
MUA ( Mail User Agent )
:
The client PC needs to use the MUA provided by the OS to process
send / retrieve. For example, the outlook express is a kind of MUA. The MUA can receive or
send the mails via the mail server, and also provide the user to read and edit mails.
MTA ( Mail Transfer Agent )
:
User need to use MTA to send / retrieve the mails. The MTA
includes 3 functions :
1.
To retrieve the mails from external mail server:The MTA will receive the mails from the
external mail server, when the recipient mail account existed in the MTA.
2.
To help user to send the mails:When the user has the authority to use the MTA, then he can
send the mails via MTA.
3.
To let the user can receive his own mails:User can receive his own mails from the mail
server.
The mail server is a kind of MTA.
MDA ( Mail Delivery Agent )
:
The MDA can deliver the mails to destination local user’s
mailbox from the MTA, or send the mails from the current MTA to next MTA.