User`s guide

MBR L13 – User’s Guide
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 To modify a rule:
1. Click the action icon for the restriction. The Restricted Website screen appears (see Figure
54: Website Restrictions).
2. Modify the Website address, group or schedule as necessary.
3. Click the OK button to save your changes and return to the Website Restrictions screen.
4. To ensure that all current IP addresses corresponding to the restricted Websites are blocked, click the
Resolve Now button. The L13 will check each of the restricted Website addresses and ensure that all IP
addresses at which this Website can be found are included in the IP addresses column.
You can disable a restriction in order to make a Website available again without having to remove it from the
Website Restrictions screen. This may be useful if you wish to make the Website available only temporarily and
plan to block it again in the future.
 To modify an entry:
1. Clear the check box next to the service name.
2. To reinstate it at a later time, simply reselect the check box.
 To modify an rule:
Click the action icon for the service. The service will be permanently removed.
3.7.1.8 Network Address Translation (NAT)
The L13 features a configurable Network Address Translation (NAT) and Network Address Port Translation (NAPT)
mechanism, allowing you to control the network addresses and ports of packets routed through your gateway. When
enabling multiple computers on your network to access the Internet using a fixed number of public IP addresses, you
can statically define which LAN IP address will be translated to which NAT IP address and/or ports.
By default, the L13 operates in NAPT routing mode (refer to Section 3.7.1.8.1). However, you can control your network
translation by defining static NAT/NAPT rules. Such rules map LAN computers to NAT IP addresses. The NAT/NAPT
mechanism is useful for managing Internet usage in your LAN and for complying with various application demands. For
example, you can assign your primary LAN computer with a single NAT IP address, in order to assure its permanent
connection to the Internet. Another example is when an application server with which you wish to connect, such as a
security server, requires that packets have a specific IP address – you can define a NAT rule for that address.
 To Configure the Network Address Translation:
1. Click the NAT link of the Firewall menu item under the Services tab. The NAT screen appears.
Figure 58: Network Address Translation
2. Before configuring NAT/NAPT rules, you must first enter the additional public IP addresses obtained from
your ISP as your NAT IP addresses in the NAT IP Addresses Pool section. The primary IP address used by the
WAN device for dynamic NAPT should not be added to this table.