Setup & Features
Both Decos are set up and managed using Android and iOS apps, which require you to surrender an email address and set up a password to enable access. Once you get the first node up, you can add more nodes via the app, which guides you through the process shown in the video below.
The video doesn't show the app testing node placement or providing guidance on where to place Decos, beyond the screens shown below. The best advice offered is to "use your phone to check" if you're within range.
Deco installation placement advice
Decos can also use Ethernet as backhaul and bypass the NAT router and run the system as APs (More > Advanced > Operating Mode).
Deco relies on a cloud relay service to support remote login and management and to keep the HomeCare antivirus signatures and parental control filters updated. But backhaul management is all handled locally.
Wi-Fi connections are limited to setting a single network name and security password and disabling SSID broadcast ("Hide this network..."). A single guest network can be enabled, too.
Deco Wi-Fi settings
App remote connection to Deco was quick and reliable. My main complaints are that you don't get an overview of how Deco nodes are connected and you can't get any information about node status. There's the usual built-in speed test that measures internet connection throughput to the root node only. But if you want to measure throughput to a node, you'll have to load a speed test app onto your device and run it there.
Deco app screens
Deco has a few features not commonly found on Wi-Fi mesh systems. Support for 802.11r fast roaming is disabled by default because it can prevent older devices from connecting reliably or at all. The Dynamic DNS feature (DDNS) will be helpful only if you're running servers on Deco's LAN that you'd like to more easily reach from the internet. The VLAN feature appears to be included because it's needed by some Asia-Pacific ISPs.
Deco fast roam (L), DDNS(C) and VLAN(R) settings
I'd be remiss (and I'm sure reminded by TP-Link post review) if I didn't mention Deco's HomeCare and Automation features. As noted earlier, Trend Micro-based HomeCare's feature set includes Parental Controls, QoS and Antivirus features. TP-Link bundles three years of HomeCare into Deco's price to better compete with eero, which charges $10/month or $99/year for eero Plus, which includes content filtering, antivirus, ad blocking and VIP support. We'll see what happens after three years; TP-Link hasn't set pricing for the subscription that it says will be required at that point.
Parental Controls are based on User profiles, which can have content-based web filters and internet time usage limits applied. An Insights feature shows sites a user visits and time spent there.
Priority-based QoS can be set by service type, but those categories are fixed. The Custom option just lets you set the fixed category sliders; it's odd that the Custom sliders include Custom itself. There's no way to find out which services, i.e. ports and protocols, are in each QoS category. The leftmost screenshot below shows you can prioritize a device or devices for 1, 2, 4 hours or always.
Deco QoS settings
The last HomeCare feature is Trend Micro antivirus protection for all devices. This protection is gateway based; no app is required. But it applies only when devices are on Deco's LAN or WLAN, not when you are away from home connected to another network.
Deco also supports IFTTT and Alexa skills. You'll find these on the app's Overview page under the hamburger menu Friends of Deco option. IFTTT has a handful of skills already defined.
Deco IFTTT (L) & Alexa (R) skills
Finally, you can link TP-Link, Nest and Philips Hue devices to Deco and set up automation sequences. This is independent of Alexa and IFTTT.
Deco Smart Home Automation
It's important to note that all the HomeCare, Automation, IFTTT and Alexa features don't work if you configure Deco to run as access points.
Deco's feature set is summarized in the tables below and you can also consult the User Guide. It doesn't provide detailed How To's for Deco's many features. But at least it exists; most mesh systems come with only a Quick Start guide...
All performance tests were done with Android app 1.6.11 and 1.2.0 build 20180711 Release 53033 firmware using select tests from the Version 10 Router process.
The iperf3 WAN to LAN and LAN to WAN throughput tests came in at 711 and 626 Mbps, respectively, highlighted in the charts below. This was not as good as Deco M5, which measured 941 and 925 Mbps. I double checked the results and made sure no HomeCare, Automation, or IFTTT/Alexa features were enabled. Still, with both directions capable of throughput over 500 Mbps, these results are unlikely to be a disqualifier for most buyers.
Routing throughput - iperf3 method
Although it's not a fair fight due to the M9+'s second 5 GHz radio, I'll be comparing with the Deco M5. The better comparison will be to the NETGEAR RBK40 Orbi ("mini"), which has essentially the same design as the M9+ and was tested in a two-node configuration.
WAN to LAN testing using the tougher HTTP method benchmarks actually shows better relative performance than the iperf3 test. The M9+ really pulls away from the other two products on the larger filesizes.
Routing throughput - HTTP Score comparison - WAN to LAN
Plot key file size: [A] 2 KB, [B] 10 KB, [C] 108 KB and [D] 759 KB file
LAN to WAN shows a pattern similar to downlink. M9+ FTW.