D-Link Xtreme N Duo Media Router DIR-855 - wireless router

We pitted the D-Link Xtreme N Duo Media Router DIR-855 against the only other true dual-band router we've reviewed, the Linksys WRT610N. The DIR-855 beat the WRT610N in overall throughput performance, but its design and desktop setup application couldn't compete. Both routers offer about the same range; the WRT610N provides slightly more coverage. Both routers are great dual-band devices; however, the D-Link costs about $60 more than the Linksys, making it difficult to recommend. Nonetheless, if you can justify the cost and need the fastest option, the D-Link DIR-855 will do the job. (For more detailed specifications, please see our specs page.)

Design and setup
Out of the box, the D-Link DIR-855 looks like a differently colored D-Link DGL-4500 . (The DIR-855 is white, while the DGL-4500 is dark blue.) The DIR-855 has three antennas attached to the back of the router--not a good design, as they crowd the network ports. The antennae are, however, removable, in case you need to install an external high-power antenna for longer range. Like most D-Link routers, the DIR-855 is wall-mountable and also comes with a vertical mount base. Similar to the DGL-4500, the DIR-855 has a top-mounted, organic light-emitting diode (OLED) Network Activity Display (ONAD) that shows more than just the network's connection status--the two navigation buttons display WAN, LAN, and wireless information via the little blue screen. However, in our tests, the screen timed out after a minute or two. The ONAD is fun to play around with at first, and is indeed useful in a number of situations, such as checking on the Internet connection, number of wireless clients, and so on, but in the long term, you might miss the regular LED status light found on most routers.

The D-Link DIR-855 includes four LAN gigabit ports and one WAN gigabit port, as well as a USB port that's designed only for Windows Connect Now technology (WCN). WCN is a feature that lets you transfer the wireless encryption key to a WCN-enabled client, such as the HP Deskjet 6840 or a Windows PC, via a USB thumb drive. This saves you from having to remember and manually enter the often cryptic encryption code. We found this feature a bit redundant, since the router also supports Wi-Fi Protected Setup (WPS), another popular method to quickly and conveniently add wireless clients to the network. Instead, we wish the USB port were for either print serving or network storage support, as in the Linksys WRT610N.

It's easy to set up the D-Link DIR-855. The router comes with a CD that contains the D-Link Router Quick Setup desktop software, which walks you though a few simple steps, including hooking up the hardware, creating an SSID, and setting up the encryption. The software, however, doesn't work if your computer has more than one wired network port, including FireWire ports. If this is the case, you will need to temporally disable ports except the one connected to the router. Alternatively, you can use the Web-based interface, which is well thought-out, responsive, and more comprehensive than the desktop application. Sadly, unlike the Linksys WRT610N, the D-Link DIR-855 doesn't come with a Mac version of its desktop setup software.

Features
Like the name suggests, the D-Link DIR-855 comes with two Draft N 2.0 access points. One of them uses the ubiquitous 2.4Ghz frequency, while the other works in the new 5Ghz frequency; the two can run simultaneously. This is the first router from D-Link that offers true dual-band operation.

The D-Link DIR-855 offers numerous network features that you can manage via a well-organized Web interface. You can set up manual port forwarding--where you map to a specific computer in the network all the information that comes to a certain port--or use the router's preset settings for different applications and services, such as instant messengers, BitTorrent, IP phone software, virtual servers, and so on. It also offers a comprehensive set of parental control tools, including Network Filter, Access Control, Website Filter and Inbound Control. These tools allow you to control the network and limit access to the Internet by specific criteria, such as limiting Johnny's computer's access to adult Web sites, or only allowing Johnny to use instant messengers during certain periods of time. The router also lets you customize its firewall to allow some services but not others.

The DIR-855 also comes with an interesting and useful feature called Guest Zone. Guest Zone lets you create up to two separate wireless networks (one in 2.4Ghz, one in 5Ghz) to be used either by guests or the open public. Any wireless client connected to these guest networks get access to the Internet, but not your local LAN resources.

Performance
The DIR-855 gave a mixed performance in our tests. On our maximum throughput test, the router registered 101.7Mbps and 77Mbps for the 5Ghz frequency and 2.4Ghz frequency, respectively--both high, though not perfect, scores that bested the LinksysWRT610N, which came in at 101Mbps and 53.3Mbps.

Even better, the D-Link DIR-855 topped our charts on its range test, where we tested the device's broadcasting signal at 200 feet. Its 2.4Ghz frequency throughput, 66.5Mbps, performed second only to its own 5Ghz frequency throughput, which came in at a whopping 85.7Mbps--the highest in Draft N 2.0 range throughput performance we've seen by far.

In our mixed-mode test, in which the router supported both Draft N 2.0 and legacy 802.11b/g clients at the same time in 2.4Ghz frequency, the D-Link DIR-855 finished about average, at 58.5Mbps.

All in all, the DIR-855 is a great performer, unless you need broad range. In our test environment (which is not the best for range), the router was only able to maintain a stable connection within about a 250-foot radius--20 feet shorter than the Linksys WRT610N's range.

Ixia IxChariot long-range tests, throughput measured indoors at 200 feet (in Mbps)
(Longer bars indicate better performance)

Throughput 200 feet

DIR-855 Xtreme N Duo Media Router from D-Link (2.4GHz)

66.5 

Linksys Simontaneous Dual-N Band Wireless WRT610N (5GHz)

64.6 

D-Link DGL-4500 Xtreme Gaming Router (5.0GHz)

49.7 

Linksys Simontaneous Dual-N Band Wireless WRT610N (2.4GHz)

47.7 

Apple Time Capsule (5.0GHz)

42.27 

Linksys N Ultra RangePlus WRT310N (2.4GHz)

28.8 

D-Link DGL-4500 Xtreme Gaming Router (2.4GHz)

27 

Apple Time Capsule (2.4GHz)

21.36 

Apple Airport Express (5.0GHz)

18.4 

Apple Airport Express (2.4GHz)

11.7 

DIR-855 Xtreme N Duo Media Router from D-Link (5GHz)

85.7 

Service and support
D-Link backs the DIR-855 with a one-year warranty available only in the U.S.A and Canada, which is a short but increasingly popular warranty for a home router. At the D-Link Web site, you will find a wealth of support information, including downloads, FAQs, and a searchable knowledgebase. The toll-free technical support phone line is available 24-7. We tried the number listed on the Web site and were able to get a hold of a support representative in less than 10 minutes. The representative was personable, knowledgeable, and helpful.