TP-Link Deco M9 Plus review: A mesh networking system for smart homes

In Technology


Note: This article was first published on 19th July 2018.

The TP-Link Deco M9 Plus. (Image source: TP-Link)

What’s this?

The TP-Link Deco M9 Plus is a mesh networking system and smart home hub built into one neat compact package.


Erm, what’s mesh networking?

Mesh networking lets you expand your Wi-Fi coverage using the same SSID.

Come on, where have you been? But, not to worry as we can fill you in. To put it briefly, it refers to a wireless system where multiple nodes contribute to spread Wi-Fi across an area and using the same Wi-Fi network name (SSID). This is particularly useful in solving the problems of Wi-Fi dead spots in homes. You know what? You should read our mesh networking guide before you continue reading this review to ensure you’re familiar with the basics.


Right, so what’s a smart home hub?

A smart home hub is a controller for all your smart home devices like your smart sensors, smart light bulbs, and what not. These devices need to connect to something so that they can be easily managed. Furthermore, some of them use low-power wireless standards like ZigBee and Z-Wave, so you need a compatible smart home hub for that too.


So the Deco M9 Plus is two devices in one?



What are its networking specifications like?

With three separate networks, the Deco M9 Plus is able to dedicate a single network to backhaul communications which boosts overall mesh performance. (Image source: TP-Link)

The Deco M9 Plus is a tri-band AC2200-class mesh networking system. Its single 2.4GHz network supports speeds of up to 400Mbps while its two 5GHz network support speeds of up to 867Mbps.

One of the 5GHz networks is set aside for backhaul communications, which frees up the remaining 2.4GHz and 5GHz network for client communications. However, if it detects heavy network traffic, it can also use the other available networks to supplement the single 5GHz backhaul network. It can use up to 50% of the other two networks, which gives it a total backhaul capacity of 1,500Mbps (867Mbps + 433.5Mbps + 200Mbps) If your home already has a LAN network in place, the Deco M9 Plus will also support Ethernet backhaul.


How is it packaged?

Unless you live in a huge home, two Deco M9 Plus nodes should be sufficient.

You can buy the Deco M9 Plus either as a pack or two or separately. A two-pack bundle is $369, whereas a single Deco M9 Plus is $199. Obviously, it makes far more sense to get the two-pack bundle.


Why no three-pack bundle?

Simply because TP-Link believes that a two-pack bundle would be sufficient for most homes. According to them, two nodes can cover an area of up to 4,500 square feet, which is more than enough for most apartments here. If you are lucky enough to be living in a large penthouse or landed property, you can purchase additional nodes to expand coverage.


Sounds great, what about ports?

Each Deco M9 Plus node has two Gigabit Ethernet ports and a USB port. The USB port is unusable for now.

It has two Gigabit Ethernet ports that can function either in LAN or WAN modes. Apart from connecting it to your main router or ONT, you can also use it to connect your LAN network for Ethernet backhaul, or you can use it to connect to other devices that require connectivity like your TV or gaming console. There is also a USB 2.0 port but that has been deactivated for now. TP-Link says it has been ‘reserved’ and might be activated in a future firmware update.


Oh, the wife asks if it will look out of place at home?

Thanks to its plain design and compact size, it is unobtrusive and blend into your homes. (Image source: TP-Link)

That’s hard to say. If your home has black wallpaper, tinted windows, and black furniture, then I suppose the Deco M9 Plus will look out of place. Personally, I find the Deco M9 Plus to be very pleasant looking. It has an all-white exterior and is shaped like an asymmetric hockey puck. Its noticeably larger than the Deco M5, but it is still relatively compact, comparatively speaking. To get a better sense of the size, it measures 14.4cm in diameter and it’s just over 6cm tall.

To give you a better idea of the Deco M9 Plus' size, here it is next to an iPhone 8 Plus.

I find it to be one of the better-looking and more stylish mesh networking systems around but I don’t speak for everyone. As the old saying goes, “Beauty is in the eye of the beholder.”


She also asks if it is easy to set up.

Yes, it is dead simple. Simply plug in the Deco M9 Plus, download the Deco app on your iOs or Android device, and follow the on-screen instructions. Adding extra nodes to the network is simple too. Again, just plug in the Deco M9 Plus, fire up the Deco app and choose to add extra Decos to the network, and follow the on-screen instructions again. That’s all there is to it. Adding nodes to the network is quick enough but I found that the Deco M9 Plus was quite slow to update its firmware. Since there was a new firmware, I had to update the firmware of each node individually and each time it took me about 5 to 7 minutes.


Mesh networking systems are usually short on networking features, what does this have?

Not much in the way of advanced settings and options.

For advanced users who want to tinkle around and set up stuff like private VPNs or changing DNS servers, the Deco M9 Plus is not the router for the job. You will want to stick to a traditional kind of router. In the case of the Deco M9 Plus, there are only a handful of settings that you can play around with including port forwarding, DHCP reservation, VLAN, and dynamic DNS. It is not much, but I reckon it should suffice for most users who don’t intend to tinker with the router beyond the initial setup.

One notable feature is the built-in anti-virus protection that part of the Deco M9 Plus’ HomeCare package. It provides real-time protection with rules continuously updated from Trend Micro. As part of the HomeCare package is QoS and also Parental Controls.

The Parental Controls options are pretty nifty and extensive.

For parents, the Deco M9 Plus has a pretty extensive Parental Control feature that gives parents a lot of flexibility in how they want to manage their children’s internet access. One nifty thing about the Parental Controls feature here is that it comes with predetermined filter levels like Child, Pre-teen, and Teen that has a default list of blocked sites. For example, selecting Pre-teen would block out a preset list of adult, gambling, and social networking sites. For Teens, the filter would block out adult and gambling sites but leave social networking sites accessible.


So what smart home kind of things can it do?

You can create automation rules with the Deco app.

For a start, the Deco M9 Plus supports Bluetooth 4.2 and ZigBee. It also works with Amazon Alexa, so if you happen to have a smart speaker that supports Alexa, you can issue voice commands to control your smart devices. The Deco M9 Plus also supports the free online rules platform IFTTT, which enables users to set up rules to manage their smart devices and sensors. For instance, you could program your lights to turn on whenever a motion sensor is set off.


Performance Analysis & Conclusion

So, how does it perform?

The TLDR version: Performance was mostly a mixed bag. The TP-Link Deco M9 Plus exhibited good range and provided good download speeds. Uploads speeds, however, was mostly quite disappointing. Overall, its performance was a match for the Linksys Velop and much improved over TP-Link’s first mesh networking system, the Deco M5.

For the rest of you who like to pore over graphs, here they are. But first, a quick run through of our test setup.


Test Setup

To test this new breed of mesh networking systems, we’ve changed our test environment, but our test setup remains relatively unchanged. We have two notebooks, one acting as a host machine and the other as a client device. The router, or in this case, node, acts as a gateway. Since mesh networking systems typically manage channel settings on their own, we will leave it that way. For systems where manual settings are possible, a channel bandwidth of 40MHz is selected where applicable, while 80MHz or more is used for the 5GHz AC band.

The client device is a 2015 13-inch MacBook Pro, which is one of the few client devices in the market to come with a 3×3 Wi-Fi receiver, allowing it to achieve wireless speeds of up to 1,300Mbps.

Here is a graphical representation of our network test setup.

To evaluate, we will be measuring the time and calculating the speed achieved when transferring a 1GB zip file. We will do multiple tests with different setups and different distances to simulate use around a typical single story flat and in a multi-story home.

Here are the test distances we used and what they represent:

  • 2m – Right beside the router
  • 5m – In an adjacent room
  • 10m – In a room that is farther away
  • 15m – To simulate extreme distances (e.g. master bedroom toilet)
  • Second story – One floor above
  • Third story – Two floors above

Here are the different TP-Link Deco M9 Plus setups we used:

  • A single TP-Link Deco M9 Plus router
  • Two TP-Link Deco M9 Plus nodes over a single floor
  • Two TP-Link Deco M9 Plus nodes over two floors

To further clarify, in tests where nodes were placed on the second or third floor, the measurement would be taken with the client device about two meters away from the node. Finally, included in the graphs are results of other mesh networking systems including the TP-Link Deco M5, Samsung Connect Home Pro, Google Wifi, Linksys Velop, and Netgear Orbi.


Single node performance

In this test, we will be looking at the performance of a single TP-Link Deco M9 Plus router in a single-story (using the different distance markers) and multi-story home. All other competitive mesh networking system results are also that of a single node setup.

The performance of a single TP-Link Deco M9 Plus router was a bit of a mixed bag. While download speeds were generally quite good, especially at the 10-meter range, its upload speeds were lacking. At 2 and 5-meter, its upload speeds were the lowest. Like the rest of its competitors, we didn’t manage to establish a meaningful connection at the extreme ranges of 15m and from the second and third floor.


Mesh performance at 15 meters

In this test, we placed a second TP-Link Deco M9 Plus node in between the first node and the 15-meter mark to create a mesh network to get signal to the problematic 15-meter mark. We did the same for other mesh networks to see how their performance would compare.

With a node in place, we got pretty respectable numbers. The Deco M9 Plus was clearly faster than the other dual-band mesh networking systems. However, it trailed slightly when compared to other tri-band systems like the Linksys Velop and Netgear Orbi.

Mesh performance on 2nd floor

In this test, we placed a second TP-Link Deco M9 Plus node on the second floor and created a mesh network to expand Wi-Fi coverage on the second floor. We did the same for the other mesh networks to see how their performance would compare.

With a node on the second floor to bridge the distance between our client device and the main router, we got mixed performance. Its upload speed was one of the highest, behind only the Linksys Velop and Netgear Orbi. Its download speed, however, was a little disappointing as it trailed the Netgear Orbi, Google Wifi, and Samsung Connect Home Pro.


Mesh performance on 3rd floor

Typically, we would place a third node on the third floor for this test, but since the TP-Link Deco M9 Plus only comes in a two-pack, results that you see here are from me on the third floor connecting to the node on the second floor in the test we did earlier.

While the other systems had a third node, I was still connecting to the Deco M9 Plus node on the second floor for this test since the Deco M9 Plus only comes in a pack of two. Despite this, the Deco M9 Plus’ numbers were very respectable, which is a testament to its range. Its upload speeds were still faster than a 3-pack Deco M5 and its download speeds were surpassed only by the Netgear Orbi.


How does it compare to its rivals?

The Deco M9 Plus' price is attractively priced for a tri-band mesh networking system with smart home capabilities.

Performance was mostly a mixed bag. Range is above average but its upload speeds were generally quite a lot poorer than its download speeds. Overall, the Deco M9 Plus was significantly quicker than other dual-band mesh networking systems and it was a good match for the Linksys Velop. If performance is a priority, the Netgear Orbi is still the outright performance king.

Performance may not be its strong suit but the Deco M9 Plus’ smart home capabilities give it a leg up against competing tri-band mesh networking systems in the market. The Velop and Orbi cannot act as smart home hubs. So if you are thinking of adding smart devices to your home, the Deco M9 Plus can streamline that process. The only other mesh networking system with smart home capabilities is the Samsung Connect Home Pro, but that’s a dual-band system and it is really pricey.

Price Comparison
Mesh networking system Price for a set of three
TP-Link Deco M9 Plus S$568
TP-Link Deco M5 S$399
Samsung Connect Home Pro S$894
Google Wifi S$597
Linksys Velop S$689
Netgear Orbi S$949

Speaking of price, that is perhaps the Deco M9 Plus’ strongest suit. At S$568 for three nodes ($369 for a pack of two, S$199 for a single node), it is significantly more affordable than its rivals. The Samsung Connect Home Pro, which is also a mesh networking system with smart home capabilities costs a whopping S$326 or 57% more! In light of its price, performance, and features, the Deco M9 Plus arguably offers the best value.

To sum up, the TP-Link Deco M9 Plus is a competent mesh networking system that offers a lot of value. Performance was a little erratic and upload speeds were generally poor, but it makes up for that with above-average range and competitive download speeds. On the design front, it has a clean aesthetic that should look good in most homes. Finally, it is one of the most attractively priced mesh networking systems in the market.