My home has ADSL & it’s a bad one

I chose my apartment for its great balcony even if it was not ready for FTTX. Welcome to Côte d’Azur, France !
No VDSL opportunity either. So I took an ADSL subscription being the only option left for my home internet access.

Turns out to be the worst ADSL ever witnessed.


I noticed that the 4G of my Smartphone was very stable at home. So I used it for my Smart TV (Netflix, YouTube) over the first months using the default android tethering feature. It works like a charm.
Due to our Rick & Morty addiction, we could consume from 300GB to 400GB per month while my mobile phone data plan is limited to 100GB with the French provider Free Mobile.

4G tethering, my mini fiber experience

So I looked for 4G providers (more designed for accommodation) to replace the ADSL at home…
Surprisingly, there is always a quota (200 - 400 GB per month) and that’s expensive! Moreover, You also need to buy/rent the provider 4G router (SIM cards locked to proprietary routers, I love it) that is also expensive. And I can’t ensure that this 4G will be as good as experienced so far with Free Mobile with my Smartphone.

Dead end in here. Unless…

Let’s Hack

Free Mobile claims to offer quota-free 4G (for mobile) for Free ADSL/VDSL/FTTH clients. I’ve been digging a bit the forums. No evidence of people using the mobile 4G for intense usage.
I noticed that it was not very clear in TOS documents either. It states that ‘they deserve the right to reduce users’ speed to maintain a good global service.’. Fair. Let’s try and see how it goes.

So I bought a second-hand 4G Smartphone and took another Free Mobile subscription dedicated for the house, linked to my ADSL subscription to activate the unlimited 4G feature. I tethered it right to the Smart TV, the biggest consumer at home by far, using the default Android tethering application. I’ve also disabled the 2G, 3G bands in the Smartphone just in case as the quota looks scoped to 4G.

By sending an SMS at 555, I can retrieve my monthly instant data consumption.

Far beyond the standard plan of 100GB, the 4G remains fast, Victory! And Netflix runs 4K videos due to the network awesomeness. 4K is pointless but that’s another story.

Integration like a boss

Let’s integrate the Smartphone into my network so all my devices can use the 4G internet source through my router. It also makes me able to revert to the ADSL seamlessly if 4G goes down.

I assume I can only tether from the Smartphone to the router only using the WIFI tether (using the 5GHz or the 2.4GHz band). It would be fastidious to try the USB Tether mode. My DD-WRT router can be configured as a WIFI repeater to catch up with the Smartphone. But doing so would make one WIFI band of my main router busy with this repeater feature. I use a dedicated WIFI repeater to convert the 5GHz Smartphone tethering to an Ethernet link of 100Mbps, that I plug right in the router.

We now have the network below:

The job is over.
The download speed of 41Mbps measured initially can be reached, but devices are bound to ~15Mbps individually, for some reason. Ping is reduced from 20ms to 40ms, not noticeable in real life.

This crazy setup uses 4 to 5 WIFIs:

  • 1 from the 4G tethering
  • 1 from the WIFI repeater that I don’t use but can’t disable
  • 2 from my DD-WRT router (2.4GHz and 5 GHz)
  • 1 from the ADSL router if I turn it on

18 months later

I was not expecting this setup to work for so long! I only encountered 3 or 4 network outages in 18 months, which were resolved by rebooting the Smartphone.

4G carriers use Network Address Translation, making ports forwarding impossible without using complex workarounds like VPN. UPnP does not work either.
The public IP address is changing almost every week but remains under a consistent IP address range. Only Google’s Gmail complained about the IP once for a potential security breach.

My best month

Final note

Please note that the use case covered in this blog entry is crystal clear against the terms and conditions of Free Mobile.
I’m bracing myself, FTTH is coming home.