DD-WRT router behind a Box
The french internet providers "boxes" all have a router function with some options, but which remains basic and very limited, letting the geeks we are unsatisfied. A good solution to this : stick a router behind the Box.
I usually buy only Linksys/Cisco branded routers, deemed compatible with alternatives firmware like DD-WRT, OpenWRT or Tomato for the most well known ones. They offer a quite wide routers line up, but for the most of people the WRT54GL ('L' for 'Linux') is going to be sufficient and will allow to access the numerous functionalities offered by DD-WRT at lower cost. The ones who need sharper services (N wifi, gigabit ethernet, NAS functionality with USB port, more memory) shall take their eyes to the upper range router models.
It's a very basic network configuration, probably one of the most common. Our LAN devices are 'hidden' behind the router, whose the role is roughly to manage the data exchanges between them in one hand, and mainly in a SOHO configuration to manage the exchanges between the LAN devices and the WAN (internet). In our case, the box will only be a simple modem, a bridge between the LAN and the WAN. We'll disable the router function on it, and it's our dedicated router who will take this role.
Disable router function from a french provider Box
Freebox (Free) Sign in to your Free account, at https://subscribe.free.fr/login, menu Internet → Configurer mon routeur Freebox and uncheck Vous souhaitez activer ce service.
Neufbox (SFR) Go to your Neufbox admin interface, which by default is located at http://192.168.1.1. Go to the menu Réseau → WAN. Check the 'bridge' modem then Apply. Read the process at the SFR assistance
Numéricâble Onto the lasts Numéricable routers (Castlenet and Ubee), there is (at last) an option allowing to disable the routeur modem from the modem, at http://192.168.0.1/RgSecurity.asp (replace 192.168.0.1 with your modem IP address if you changed it). nb : the process for Netgear modems is detailed at Numéricâble assistance. nb2 : you may need, depending of your modem firmware version, to connect as MSO to see this option.