Identifying Wi-Fi issues and replacements

For the last few months, my 5 year old Asus RT-AC68U wi-fi router has been dropping connections. I tried adjusting management channel, checked for local interference in the house or with other wi-fi networks, and eventually did some signal checks with NetSpot running on the Windows 10 laptop.

From looking at the NetSpot graphs above for both 2.4GHz and 5GHz, it looks like that the whole signal was dropping off a cliff increasingly often, leaving pages not loading and in some cases devices being disconnected. I tried aerial adjustments and other things on the unit, rolling back firmware, doing factory resets, but to no avail. Also the small satellite range extender didn’t seem to help at all.

Due to working from home and kids studying at home, this just wasn’t going to work and having done the troubleshooting without any tangible results and from what I was reading in forums, it seemed to point to a hardware issue. It was time to dump the unit(s) and move to something else.

I know around the time I got my router, Asus were somewhat infamous for ASUSgate but the unit I had was apparently fine at least for that and generally it had performed well, but I decided to have a look at what was on the market rather than simply looking at what new Asus had.

Wifi6 is here but expensive and I wanted something with that new fangled mesh technology for the house devices which I could also add to later, so after reading reviews and checking the bank account, I’ve gone for the TP-Link Deco M5 (x2).

They’re small, inconspicuous, or at least not obnoxious in design, and the devices and app got good reviews wherever I looked. They’re .ac / wi-fi 5(?), but that’s fine because all of my stuff is too and likely will be for a while. They’re now installed and so far performance seems fine for my simple wi-fi needs and I also set up the optional wired ethernet backhaul channel which should help.

There is a web interface for the Decos on the local LAN which has very limited functionality as they’re intended to be managed via a phone app which itself requires a TPLink account to log in. Once that was done it was quick to set up and get running, and unlike the Asus, was very clear when the backhaul was working. As far as the app and configuration, I think it’s fine, but yes, I am always concerned when I need to go through a company server to access the wi-fi access point I’m looking at, but that certainly seems to be the way these things are now in the IoT world (where the ‘s’ stands for security). On the upside, I can do firmware updates when I know we’re all out of the house (…).

That said, it was simple to set up my usual things of limiting usage hours for the kids, pointing to specific DNS servers (my PiHole) and generally get a list of devices, check their MACs and give them human readable names. I was also able to setup browsing profiles.

Like many of these devices, this has a series of Trend Micro malicious site and Intrusion Detection Systems. It would be good to know how these are working - is data being shipped off to Trend or is this being done locally? It does note the database date on the screen which suggests locally and unlike the Asus, there’s no additional fee. The Asus would show options, the say you had to pay extra for it. Kind of annoying; I appreciate some subscription are worth it, the way it was presented on the Asus felt a bit bait and switch on some of the features.

Port-wise it seems to have the ports I’d expect such as DNS and HTTPS open, and a quick nmap scan didnt show anything unexpected in use. That’s not too bad. When I get chance I’ll see if it does much in the way of calling home traffic. I do try to keep an eye out for security bulletins mentioning TP Link units.

So how are they to use? In short, fine. No complaints from the family, and signal and sessions look solid all over the house, and for the money (~14,000JPY / 175 USD) it’s quite impressive. The individual units lack ethernet ports, just one for an uplink and one a downlink, so it’s hooked up to a switch for capacity. Also, the backhaul uses a wired connection between the two access point works really well, and so doesn’t eat up a chunk of bandwidth and processing to let the Decos route traffic. On the Asus, it was never clear whether it was using the backhaul between the extender and the main unit effectively.