Port Forwarding on Router Not Supporting It

[daniel_i_l]

Is it possible to do port forwarding if my router doesn't support it? (I can't upgrade the firmware because it's not my router, and I can't switch routers because the router contains the modem from the ISP).
I was thinking that maybe it'd be possible to use NAT in order to simulate port forwarding. Is it possible to send certain requests to the router from inside the LAN so that it forwards signals from outside the LAN (on a specific port) back to that computer using NAT?
Or maybe it'd be possible from outside the LAN, to send a signal to the router that'd cause it to broadcast a message to the entire LAN on an obscure port. Then only one computer would be listening on that port.
Could any of these ideas work?
Are there other options?
Thanks

 

[Ronnin]

Not exactly sure why your router doesn't support NAT, but if it's not configurable I would opt for setting up a proxy server. You can take an old computer as the proxy. Have that machine stand between your router and your LAN. Therefore it would act as your configurable router. You will loose some performance in the network doing it that way but you would be able to have all the functionality you are looking for vs. trying to find a workaround for the router.

 

[daniel_i_l]

I would opt for setting up a proxy server. You can take an old computer as the proxy. Have that machine stand between your router and your LAN. Therefore it would act as your configurable router.

I'd like to do that but the modem is inside the router. The adsl line does straight into the router.

 

[Ronnin]

It still can be done but you'll need some more hardware. You'll have your router/modem connected to the proxy PC though one network card, you'll have to setup another network inside that same machine to bridge the connection. Then from that you would need another switch to tie all your network machines together to the proxy.

Or...

Add a second router to the network after your phone co's router. Have it grab the IP just like your computer is now and have that act as the network's gateway. That would be the simplist solution but you could run into issues if you have zero config on the phone co's router. I would borrow one before I buy just to see if you could get it to work.