ESET North America Server NOD32 사용자 설명서
Chapter 3. Mail server in UNIX OS environment
This chapter is concerned with the basics of the e-mail messaging system, also commonly called
e-mail server system, however, e-mail server is only part of the more complex messaging system.
For better understanding of the NOD32LMS operation, knowledge of the messaging system
basic principles is of paramount importance. Therefore we do not recommend to skipping this
section unless this knowledge is already acquired.
The following diagram is a rough scheme of the UNIX OS e-mail messaging system.
e-mail server system, however, e-mail server is only part of the more complex messaging system.
For better understanding of the NOD32LMS operation, knowledge of the messaging system
basic principles is of paramount importance. Therefore we do not recommend to skipping this
section unless this knowledge is already acquired.
The following diagram is a rough scheme of the UNIX OS e-mail messaging system.
Figure 3-1. Scheme of UNIX OS e-mail messaging system.
MDA
MAILBOX
MTA
MUA
INTERNET
E−mail Server
PIPE
FILE
Clients
Computer
Computer
(SMTP)
TCP PORT 25 (SMTP)
TCP PORT 110 (POP3)
OR 143 (IMAP)
TCP PORT 25 (SMTP)
S1
S2
S3
Client
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