Performance - 2.4GHz
To simulate a wireless network scenario, our routine test setup includes a desktop PC, the reviewed router, and a wireless client. The desktop system (with a Gigabit Ethernet port) is designed to simulate a host machine, while the router in question acts as the gateway. And lastly, an external dual-band 802.11n USB adapter plugged into a notebook fulfills the role of a wireless remote client. However, since the RT-AC66U is an 802.11ac-based router and there aren't any viable 802.11ac wireless adapters as yet, we'll be testing the device's throughput speeds with another RT-AC66U configured in "media bridge" mode. This secondary RT-AC66U will act as a stand-in adapter for the 5GHz AC band.
To gauge the router's peak potential and to prevent any possibility of varying wireless standards used, the evaluated router is locked down at the 802.11n-only mode for both bands. Typically, channel bandwidths of 40MHz, and 80MHz (for 5GHz AC band) are selected where applicable. The QCheck application measures the wireless throughput (TCP) and streaming (UDP) finesse between the host and client endpoints based on a 1MB data packet. On the other hand, NetIQ's Chariot benchmark offers a more detailed account with average throughput and response time readings recorded over 30 seconds, based on a High Performance throughput script. Range is determined by the distance between the router and wireless client. Now, let's run through the results proper.
Chariot and QCheck Performance Testing (2.4GHz Band)
|Average Downlink Throughput (Mbps) - Chariot||Average Uplink Throughput (Mbps) - Chariot||Downlink TCP Throughput of 1MB (Mbps)||Uplink TCP Throughput of 1MB (Mbps)||UDP Streaming (kbps)||Time to transfer 1GB Zip file|
|35.515||53.836||40.816||28.532||998.732 (0.0% loss)||3 minutes 21 seconds|
|30.646||32.610||29.963||26.936||1,000.480 (0.2% loss)||3 minutes 22 seconds|
|25.512||31.504||22.923||33.058||1,002.237 (0.0% loss)||N.A.|
|2m with WPA2-Personal|
Before we proceed, do note that we've clamped the router's channel bandwidth to 40MHz to derive the best possible data rate from the networking device. Now, let's look at the RT-AC66U's average downlink measurements. A quick glance of the router's 2.4GHz throughput results below would tell you that it wasn't too impressive, with only an middling performance to show at best. However, we have to admit that the numbers are a little puzzling, given that the it shares similar hardware to the RT-N66U apart from the 5GHz chip. At 2 meters, for instance, the N66U clocked 72.108Mbps, and this figure was closely matched by the Edimax and Trendnet routers. The AC66U, however, only managed to scrimp by with 35.515Mbps, which was just about half of what its predecessor achieved. Given its theoretical top speed of 450Mbps, it's quite a shame that the router did not come anywhere near it. The same pattern was repeated with WPA2 encryption enabled. At 10 meters, the RT-AC66U finished with an average result of 30.646Mbps, although it did offer a better signal range at 25 meters than the Edimax and Trendnet offerings. The router's uplink performance was also comparable to its downstream results, finishing at 53.836Mbps at 2 meters, and 31.504Mbps at the farthest distance of 25 meters. Although the general rule of thumb states that a minimum bandwidth of 25Mbps is required for HD streams, we wouldn't recommend using the RT-AC66U's 2.4GHz band for such a purpose just yet. It would suffice, however, for your day-to-day surfing needs.