User's Manual

Firewall
Configuring the NAT Rules to Securely Access a Remote Network
Cisco ISA500 Series Integrated Security Appliance Administrator Guide 195
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STEP 5 Click Save to apply your settings.
Configuring Port Forwarding Rules
Port forwarding forwards a TCP/IP packet traversing a Network Address
Translator (NAT) gateway to a pre-determined network port on a host within a
NAT-masqueraded, typically private network based on the port number on which
it was received at the gateway from the originating host.
Use the Port Forwarding page to assign a port number to a service that is
associated with the application you want to run, such as web servers, ftp servers,
email servers, or other specialized Internet applications.
NOTE You must create a firewall access rule to allow the access so that the port
forwarding rule can function properly.
NOTE To open an internal FTP server to Internet, make sure that the internal FTP server is
listening on TCP port 21 or the FTP server and client must use the active mode
when the internal FTP server is listening on some other TCP port. Otherwise the
FTP client cannot access the FTP server.
STEP 1 Click Firewall -> NAT -> Port Forwarding.
The Port Forwarding window opens.
STEP 2 To add a port forwarding rule, click Add.
Other Options: To edit an entry, click Edit. To delete an entry, click Delete. To
select multiple entries, check the boxes of multiple entries and click Delete
Selection.
After you click Add or Edit, the Port Forwrding - Add/Edit window opens.
STEP 3 Enter the following information:
• Original Service: Choose an existing service as the incoming service.
• Translated Service: Choose an existing service as the translated service
that you will host.