Cisco Cisco Email Security Appliance C390 사용자 가이드
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Chapter 5 Configuring the Gateway to Receive Email
5-4
Cisco IronPort AsyncOS 7.5 for Email Configuration Guide
OL-25136-01
Figure 5-2
Using the Cisco IronPort Appliance as an Enterprise Gateway
In this configuration, at least two listeners are required:
•
One listener configured specifically to accept mail from the Internet
•
One listener configured specifically to accept mail from your internal
groupware and email servers (POP/IMAP)
groupware and email servers (POP/IMAP)
Public and Private Listeners
Consider the first listener a “public” listener and the second listener a “private”
listener. Cisco IronPort AsyncOS differentiates between public listeners — which
by default have the characteristics for receiving email from the Internet — and
private listeners that are intended to accept email only from internal (groupware,
listener. Cisco IronPort AsyncOS differentiates between public listeners — which
by default have the characteristics for receiving email from the Internet — and
private listeners that are intended to accept email only from internal (groupware,
Internet
Groupware server
(Exchange™, Domino™,
Large Small
ISPs
IronPort Email Security appliance
SMTP
SMTP
Groupware client
Groupwise™)
corporations
corporations
POP/IMAP server
POP/IMAP client
Firewall