Page 2 - Physical Look - Hardware
As with most mesh routers, the TP-Link Deco X90 is expected to be placed in a spread-out area around the house for the best distribution of Wi-Fi signal. Thus, these units generally should take up less room and better at hiding into your daily living area. The TP-Link Deco X90 units, however, are a bit larger than what you might expect for a node. In terms of dimensions, each Deco X90 unit is approximately 130mm in width, 123mm in depth, and 210mm in height. These take up quite a bit of space in the open, especially with its taller height. With a flared cylindrical shape, it is not exactly clear that this is a piece of technology unless you take a closer look at it. On first look, it reminded me of a paper towel roll with a hanging piece, but the appearance grew on me over time. As for its construction, the whole unit is made up of a matte white plastic with a glossy area on the top. The white finish looks modern enough to blend into a home environment. On the overlapping areas on the side, there is a TP-Link company logo on one side and a "deco" name on the other. A slim diffuser area houses an LED indicator light near the deco name to indicate the status of that particular unit. This can vary between a solid or flashing yellow, blue, and green color, each with their own meaning depending on the context.
Internally, each unit houses a 1.5GHz quad-core processor and six internal antennas. You might be wondering, why do we need so many antennas? The first reason is the fact the TP-Link Deco X90 system requires extra antennas to communicate with each other over a wireless backhaul. The TP-Link Deco X90 does support a wired backhaul too, but not every user may have the infrastructure to support this operation. On the client side, the use of multiple antennas for communications has been the foundation of many modern wireless technologies; ranging from short range unlicensed bands such as Wi-Fi to long range licensed bands like 5G cell phone networks. The fundamental principle lies in the fact that multiple antennas allow the designer to enhance performance using beamforming and diversity techniques. Beamforming, in the simplest explanation, allows power to be directed towards a certain direction. Diversity exploits multipath -- where the same signal can arrive via different paths due to reflection and refraction in the propagation channel -- to enhance the received signal quality. Multi-user MIMO, otherwise called MU-MIMO, lets multiple antennas from multiple users to communicate with multiple antennas on the base station. Obviously, the more antennas on the access point the better, but we are bound by the laws of diminishing returns.
The two nodes in the TP-Link Deco X90 system is an AX6600 wireless access point. This means it operates at 574Mbps on the 2.4GHz band via one 40MHz channel with two spatial streams and one 80MHz channel with two streams on the 5GHz band provides 1201Mbps. An additional 4804Mbps of bandwidth on a 160MHz channel with four streams also on the 5GHz band gives it 6579Mbps total theoretical throughput for its AX6600 designation. The two 5GHz bands are separately operated connections. We will evaluate the performance of this router in just a moment.
Flipping to the bottom, you can see we have a ring of ventilation at the bottom, which allows air to pass through in here and out the top. Four rubber feet surround the bottom of the Deco X90 to provide some clearance and stability for where these nodes will sit. At the bottom, we have a 12V DC power input and a pinhole reset button. On the side, we have a 2.5 Gigabit Ethernet port and a Gigabit Ethernet port. Either of these can be used for the uplink WAN port. It is a bit of a shame we only have a total of two Ethernet ports here, especially when one of them will be occupied by the WAN cable. The other omission I should note is the lack of any USB port on either of the Deco X90 units, which is more common on single router units. Moving on, the power supply that connects here is an external brick with a product number T120250-2B4 and is made in China. Finally, a routing hole is located at the bottom so that the power cable can lead out the bottom while the Deco X90 node sits flat on the surface. In the middle of the base is a label showing information like the serial number, default SSID, and MAC address. You will probably want to change your SSID once you get it set up, but this is just the default one so you can connect to it.
1. Introduction, Packaging, Specifications
2. Physical Look - Hardware
3. Configuration and User Interface
4. Performance Tests