Advanced Setup
8
To delete a custom application, click the
Delete a custom application
link. The following page is displayed:
9
Select the application you want to remove from the drop-down list and
click the
Next>
button. A confirmation page is displayed where you
click the
Confirm Changes
button.
In order to access your custom application, you must first enable it. See
section 5.4.5 - ”Configure Internet Applications”.
5.4.7
Application Level Gateways (ALGs)
There are certain difficult applications that NAT and Firewall configurations
cannot manage. In many cases, Application Level Gateways (ALGs) are
needed to translate and transport packets correctly.
An ALG provides a service for a specific application. Incoming packets are
checked against existing NAT rules or Firewall filters, IP addresses are
evaluated and detailed packets analysis is performed. If necessary, the
contents of a packet are modified and if a secondary port is required, the
ALG will open one. The ALG for each application does not require
additional configuration.
ALG support is provided for the applications listed in the table below:
1553-ZAT 759 94 Uen B – July 2005
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