Specifications

IPv4 and IPv6 Internet and WAN Settings

ProSAFE Gigabit Quad WAN SSL VPN Firewall SRX5308

6. (Optional) Configure the WAN options. If necessary, change the factory default MTU size,

port speed, and MAC address of the VPN firewall. These are advanced features, and you

usually do not need to change the settings.

These tasks are described in Configure Advanced WAN Options and Other Tasks on

page 71.

Configure the IPv4 Internet Connection and WAN

Settings

• Configure the IPv4 WAN Mode

• Let the VPN Firewall Automatically Detect and Configure an IPv4 Internet Connection

• Manually Configure an IPv4 Internet Connection

• Configure Load Balancing or Auto-Rollover for IPv4 Interfaces

• Configure Secondary WAN Addresses

• Configure Dynamic DNS

To set up your VPN firewall for secure IPv4 Internet connections, you need to determine the

IPv4 W

AN mode (see the next section) and then configure the IPv4 Internet connection to

your ISP on the W

AN port. The web management interface offers two connection

configuration options, described in the following sections:

• Let the VPN Firewall Automatically Detect and Configure an IPv4 Internet Connection on

page 31

• Manually Configure an IPv4 Internet Connection on page 34

Configure the IPv4 WAN Mode

By default, IPv4 is supported and functions in NAT mode but can also function in classical

routing mode. IPv4 functions the same way in IPv4-only mode that it does in IPv4 / IPv6

mode. The latter mode adds IPv6 functionality (see Configure the IPv6 Routing Mode on

page 53).

Network Address Translation

Network Address Translation (NAT) allows all computers on your LAN to share a single public

Internet IP address. From the Internet, there is only a single device (the VPN firewall) and a

single IP address. Computers on your LAN can use any private IP address range, and these

IP addresses are not visible from the Internet.

Note the following about NAT:

• The VPN firewall uses NAT to select the correct computer (on your LAN) to receive any

incoming data.

• If you have only a single public Internet IP address, you need to use NAT (the default

setting).