Tenda D303 is an All-In-One Device that includes Wireless-N 300Mbps router, four-Port Ethernet switch, 3G and NAS in one unit. The device provides triple WAN ports for broadband connection to ensure an uninterrupted connection. It connects to high speed network through DSL or Ethernet connections. Also, by simply plug an activated 3G USB modem, the device connects to a mobile broadband. So when the DSL/cable connections is disconnected, it will connect to a mobile network. When DSL/cable connection is restored, it reconnects to reduce connection billing. Hence, the D303 is an ideal solution for office situations where a constant and uninterrupted connection is critical, or residences where fixed broadband connection is not available.