Security Firewall Routers provide Layer2 security as well as Bandwidth management, Content Management and VPN tunneling on most models.
As well as the primary ADSL interface, some models feature a secondary WAN port for Internet access. This is an Ethernet interface and can connect to a second ADSL modem, cable modem or any other Ethernet-based Internet feed. The secondary interface can be used either for WAN-Backup or load balancing.
The USB port provides an alternative connection method for Internet backup by connecting to a compatible USB modem (or cellphone) for access to the high speed 3G cellular networks or to connect a USB Network Printer. If you don't have ADSL at all, the USB/3G access method can be used as your primary/only Internet connection, ideal for temporary locations, mobile applications or where broadband access is not available. In addition you can instead connect a compatible analogue modem to use analogue dial-up connections for failover in the event of your broadband failing. See separate page for more details on both 3G and analogue dial-up.
Business Class, 3G, DSL Bonding and Dual Wan Routers