ASUS RT-AC87U Wireless-AC2400 Dual-band Router Review
THE RT-AC87U IS the first router we’ve seen to support multiple-user MIMO (MU-MIMO), which allows the router to send data to up to four client radios at the same time. This is an improvement on current MIMO technology that communicates with each client one at a time. Once MU-MIMO is more widely adopted we should see big wireless networking improvements in multi-user environments.
The four external antennas at the back of the router are upgradable. There’s a Gigabit Ethernet WAN and four Gigabit Ethernet LAN ports for wired devices. Either the front USB3 (hidden behind a flap) or rear USB port can be used to share external storage on your local network. Both FTP and SMB sharing are supported and you can create a DLNA or iTunes server for your media, though we couldn’t get the iTunes component to work. The AiCloud app for Android and iOS lets you access your files on a smartphone or tablet, while AiDisk lets you access files remotely over the internet.
Printer sharing requires you to install the Asus printer utility on each computer, and you can connect a 3G/4G USB dongle or even an Android phone to share its data connection. The router has presets for common providers, or you can enter your SIM’s APN settings manually. Our test Vodafone dongle worked perfectly after a router reboot. The RT-AC87U also has a new feature called AiProtection. This uses Trend Micro technology to detect malware before it reaches any devices on your network.
When testing with our 802.11n laptop, we saw 36.5Mbit/s at 10m and 16.4Mbit/s at 25m on the 2.4GHz network, which is average. On the 5GHz band this increased to an enormous 209.7Mbit/s and 135.2Mbit/s; incredible results at both ranges, and quicker even than a wired 10/100 Ethernet connection. Asus couldn’t send us a wired USB adaptor for testing, so we used our reference Trendnet TEW-805UB 802.11ac USB3 adaptor. With the router in 5GHz 802.11n mode, we saw speeds of 181.8Mbit/s at 10m and 109.9Mbit/s at 25m, which are reasonable if not spectacular. In 802.11ac mode throughput leapt up to 279.6Mbit/s and 139.8Mbit/s; the 10m speed is up there with the best, and the 25m score is above average.
Neither our laptop nor the USB adaptor support TurboQAM, so we weren’t seeing the router at its best. Until Asus releases its PCE-A87 PCI-E adaptor later in the year, the only way to take advantage of the RT-AC87U’s full speed is to use a second router in media bridge mode. With a second router set up, we saw astronomical speeds of 699Mbit/s at 10m and a still amazing 419Mbit/s at 25m. Even without the luxury of a second router, the speeds from the RT-AC87U are good across the board, and its extra features such as AiProtection are useful. It also has some of the fastest speeds we’ve ever seen in 5GHz 802.11n mode at 25m, so if you want the best possible speeds for your laptop it’s a great buy – but at a price.