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I have a wireless router / ADSL modem and a 3G card that I use to connect to the internet over PPP.

I want to be able to share my internet connection (ppp0) to my laptop via the wireless router. So my setup looks like this:


internet <=(ppp0)= desktop =(eth0)=> ADSL router

Now from my laptop, I want to connect to my ADSL router (which has built-in DHCP, not sure if that is a problem), so that I can use the internet connection on the desktop.

laptop =(wlan0)=> ADSL router => desktop => internet

Hope this makes sense.

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up vote 0 down vote accepted

Without getting into the technicalities of it, you will have to disable the routing and DHCP of your ADSL modem, and make sure the wireless is bridged. So there is work to be done on the router first. You basically have to turn it into a dumb AP. Once you do that, you can enable DHCP and routing on the ETH0 adapter so that those that connect to the AP can receive an IP and route out the ppp0 interface. Hope you are comfortable with editing the /etc/* in a CLI based text editor cuz there is not a simple GUI fix for it.

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Thanks Frank. Sounds like I would have to enable packet forwarding on the router, or something(?). I am happy with CLI, but my networking knowledge is yet very basic. Not sure whether my modem will allow me to change settings on it, so it seems I might have to invest in some other hardware. Many thanks. – mydoghasworms Mar 15 '12 at 5:52

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