@LesterAlzaga 

With what you have, your plan is the best. Replace your Access Point by Deco node, it'll be Main Deco in TP-Link terminology. Run Deco mesh in Access Point mode. Place two remaining Deco nodes, which will be Satellite Deco, around the house to improve WiFi coverage.

Just one thing: are you aware that Deco E4 has 100Mbps Ethernet ports? Whatever is connected to them, won't be getting Internet speeds faster than that.

If your Internet speed is under 100Mbps and you don't expect to upgrade it to faster speeds in the foreseeable future, Deco E4 can do just fine. Otherwise, get different Deco hardware, with gigabit Ethernet ports. If you decided to go with different Deco hardware, I would recommend Deco M5.

  @Alexandre. 

Thanks for your advice. I have done just that and it works great.

I am wondering though,

What if... I connect the main Deco to my Router and then to the Switch...

• Will it work?
• Can the Deco work in Router Mode?
• How will this affect my network?
• Compared to my current setup (using Deco in Access Point Mode), which will be better?

Regarding you comment on the speed limit of E4; it's completely fine with me since I have just 50Mbps internet speed. I used to get about 20Mbps from my previous access point but after installing the Deco E4, I can reach the maximum 50Mbps.

  @LesterAlzaga 

I suggest you keep your network layout as is. Also, in Access Point mode, you can wire two Satellite Deco anywhere you want, as long as there is Ethernet cable. For example, if you want strong WiFi signal near one of your wired PCs, just plug Deco E4 to the Ethernet cable that was going to PC and plug PC to the second port of that Satellite Deco.

Of course, Satellite Deco can also run wirelessly connected to Main Deco, too, but wired will always beat wireless in reliability of connection.

Usually, people run Deco mesh in Router mode to remove old router they have. Yours is dual WAN router, judging from the diagram. You can't replace it with Deco.

You can run Deco in Router mode, then you have to put Main Deco between Router and Switch. How will this affect your network? Think of generic WiFi router. If you plug it between your dual WAN router and switch, it'll affect your home network the same. All Internet traffic will pass through that generic WiFi router, then through dual WAN router. It will work, unless you start getting "Double NAT" complains from XBox or VPN service. Yes, it will work, but, why?

  @Alexandre. 

I fully intend to keep my network layout as it is.

The only reason I'm asking these questions is because I'm relatively new to using a mesh (and the Deco specifically). I'm just trying to learn and explore all possibilities and the capabilities of this technology.

Thank you again for all your answers, it really helped me learn a lot.