using NetFilter to share the SAME SINGLE IP between a Linux
router AND a computer simultaneously
gdh at acentral.co.uk
Mon Jun 20 16:02:00 CEST 2005
On Monday 20 June 2005 14:31, John Wigley wrote:
> Before anyone says that this is mad and that it can't be done, it can be
> done perfectly well and all WESTELL ADSL / Ethernet routers have this
> functionality along with some no name Far Eastern origin broadband routers
> based on a Conexant OEM reference design.
I'd just like to add weight to this call - it's certainly been done in these
cheapy routers, usually called 'PPP Half Bridge'. The router terminates the
PPP session, and still launches a DHCP server for the LAN, which will only
ever give out one lease, the public address allocated by the ISP, and it does
some majik to translate between them.
However, there is another option...
This morning for the first time I used a Linksys ADSL2MUE device and was
disappointed to find that it did not support port forwarding or DMZ host.
Even in the UK with BT's PPP-over-ATM setup, what you can do is configure the
modem in 'Bridge only' mode - you do not give the modem your ADSL username
Then you run 'pppoeconf' in Linux (yes, PPPoE !) and give it your ADSL
user+pass - it will give you a ppp0 device set with the public IP address so
you can easily assign QoS and proper firewalling to it :))
Well worth a look!
More information about the netfilter