I used an laptop equipped with a 2.5GHz Intel Core i5-3210M CPU, 4GB of memory, and an integrated Intel Centrino Ultimate-N 6300 Wi-Fi adapter to run my benchmark tests. The Ultimate-N 6300 can send and receive three simultaneous 150-mbps spatial streams (450 mbps in total); most adapters are limited to handling two (300 mbps in total). This was all the streaming I needed to evaluate the WZR-D1800H's 802.11n performance (on both the 2.4GHz and 5GHz frequency bands). To measure the router's 802.11ac performance (on the 5GHz frequency band), I used Buffalo's AirStation AC1300 wireless ethernet bridge, connecting the bridge to the AVADirect's ethernet port. The bridge looks almost exactly like Buffalo's router from the front. It has a four-port gigabit switch in the back, but it lacks a WAN port.

To test the router, I positioned the client successively at five spots inside and outside a 2800-square-foot, ranch-style home (distances from the router are noted in each chart below). I used the open-source IPERF benchmark (and the JPERF Java graphical front end designed for it). To measure the router's downlink TCP throughput, I set up the laptop as a server and used a desktop PC hard-wired to the router as the client.

The WZR-D1800H delivered disappointing performance at close range, with the client 9 feet away from the router and in the same room. It might sound odd to hear a wireless TCP throughput of 270 mbps described as disappointing, but the Asus and Netgear routers delivered TCP throughput approaching 500 mbps. Only the two-spatial-stream Belkin AC 1200 delivered slower performance than Buffalo's router at this location.

As you can see in the chart , things didn't improve any when I moved the client and the wireless bridge to the kitchen. Here again, the WZR-D1800H finished ahead of only the Belkin AC 1200 DB, delivering wireless TCP throughput at 269 mbps, compared to the Netgear's nearly 500 mbps and the Asus's astonishing 525 mbps.