Nokia IP60 - Security Appliance, Руководство пользователя

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Using NAT Rules
Chapter 12: Setting Your Security Policy 257
How Does Hide NAT Work?
In Hide NAT, traffic to and from the internal networks traverses an enforcement module. When a packet
from an internal network passes through the gateway, the source IP address is changed to the hiding IP
address, and the source port is changed to a dynamically assigned port that uniquely identifies the
connection. The relationship between the dynamically assigned port and the internal IP address is recorded
in the gateway’s state tables. When reply packets arrive, the enforcement module uses the destination port
to determine to which connection the packet belongs, and then adjusts the destination port and IP address
accordingly.
Adding and Editing NAT Rules
This procedure explains how to add and edit custom NAT rules. You cannot add or edit an implicitly
defined NAT rule directly.
To add or edit a custom NAT rule
1. Click
Security
in the main menu, and click the
NAT
tab.
The
Address Translation
page appears.
2. Do one of the following:
To add a new rule, click
New
.
To edit an existing rule, click the Edit icon next to the desired rule.