DrayTek's Vigor 3900 is a multi-WAN router that performs a similar task to the Vigor 3200n. It’s designed to provide redundancy for medium to large businesses that have more than one internet connection - should one fail, it'll automatically divert traffic to the second connection and allow business to continue as normal.
Given the huge difference in cost between this £617 router and the £375 3200n, you might expect to find a few differences. Whereas the 3200n looks very much like a consumer router, available as either a rack-mountable or standalone device, and is supplied with wireless functionality, the Vigor 3900 is better suited to medium to large businesses. This unit must be rack-mounted, and it lacks Wi-Fi.
Pricewise, the DrayTek Vigor 3900 is pitched more closely to the high-end routers built for enterprise networks from Cisco and the like. Unlike those devices, however, this router can be configured without you needing to hire external support staff. That's important: maintaining a large network can easily become more expensive than the cost of the hardware itself.
The 3900 has a similar battery of ports to its sibling. Four WAN connections let you hook up multiple internet links, with load-balancing and traffic-routing rules. One of two LAN ports can be used for a demilitarised zone (DMZ), or a web or FTP server; the other lets you isolate the company network, reducing the risk of a successful web intrusion gaining access.
The 3900 has two small-form-factor pluggable (SFP) ports for fibre-optic networking: one can be used as a WAN port; the other for a local fibre network. A console port is also present, allowing a dedicated computer to be used for configuring the router. Finally, two USB 2.0 ports let you add a 3G modem or external storage. Given that this is a professional-level router, though, we'd have hoped for USB 3.0 connectivity, too.
With four LAN connections and two 3G failover options, we can't envisage a realistic solution where internet access would be entirely lost with the DrayTek Vigor 3900... unless the device itself fails, of course. DrayTek has considered this shortcoming, and programmed in a High Availability feature that lets you configure a spare Vigor 3900 to automatically take the controls when required. A master/backup relationship means your settings are mirrored on each device.
DrayTek has also upped the ante in terms of virtual private network (VPN) capabilities for the 3900. This multi-WAN router supports up to 500 VPN tunnels; the 3200n is limited to 32. That said, only 200 are available with SSL encryption. You can add a second layer of security for remote workers, with a mobile app allowing the use of one-time passwords. Multiple WAN connections can also be dedicated to a single VPN tunnel between remote offices, providing a high-bandwidth reliable link between your firm’s various sites.
The onboard administration software is a cut above anything we’ve seen supplied with competing routers, including DrayTek’s own line-up. It's extremely responsive, and offers a great deal of useful information. The dashboard displays the network load for both IPv4 and IPv6 traffic, plus the CPU and memory usage. You can view tables for DHCP, routing and load balancing, and the firewall allows you to block traffic based on IP, port or even MAC address. DrayTek’s comprehensive web content filtering is also available on a subscription basis.