Instructions for setting up a hardware ZyWALL USG series gateway using a static IP address for connecting to the Internet – Zyxel Support Campus EMEA
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Amazon.com: Zyxel ZyWALL USG50 Internet Security Firewall with Dual-WAN, 4 Gigabit LAN/DMZ Ports, 5 IPSec VPN, SSL VPN, and 3G WAN Support : Electronics