Hey,

Networking has never been my strong point as I've never had more than one computer to experiment with. I do now though and the first thing I want to do it use it to replace my crappy modem/router that keeps dropping my ADSL connection at very inoppertune times I have a USB modem that I've already configured, here is a quick pic of my network setup:
Rather than buy any more network cards I just want to use my 4-port router as a switch. Yesterday I had a play around and I turned off the NAT and all that sort of jazz in the router, got the gateway PC connected and online and then set it's IP as my gateway but I couldn't access the outside world from PC1 at all. Ummm, not sure what to try next

If anyone knows of any guides, software etc that I'd need links would be appreciated. My main problem I think is I don't know how to make the router transparent or make PC{1,2,3} see through it to gateway to get their net access. I'll find something to run on the gateway to handle routing etc but yeah, any pointers would be appreciated as this is my first real play in networking and I'm stumped

Thanks

Umm... I'm a bit confused with your diagram. Do you have a modem and a router between your computers and the internet or do you also have a "gateway". In other words, do you have 5 devices (including computers) or 6.

What kind of modem (let me guess, Actiontec?)
What kind of router?

Alright, the diagram could suck. The modem is just a stock ADSL USB modem, I've got that working so that's all good. Gateway is just a computer, I was originally planning to chuck some more ethernet cards in it and lose the router but if I can use the 4-port switch in my router to save $30 then that sounds good to me. All up I have 6 devices including the modem, basically I just want the router/switch to be transparent to PC{1,2,3} because they're accessing the internet through all of that. I don't know if running a dhcp server on the gateway (PC) would work because they'd have to go through the switch first.

Am I making any sense or should I just buy some PCI ethernet cards so then I know what I'm doing?

Even if you turn off NAT, your router is still a router and not a switch. So PC1,2,3 still have to have the address ofthe router as the gateway. The only thing you do by turning off NAT is expose the downstream address space of that router to upstream systems. The downstream systems still use the router as their gateway.

If you want a switch, buy a switch. Personally, I would just use the router.

I'm a bit confused as to why the "gateway" computer is there. Are you trying to set it up as a router or a proxy server? If so, what OS does it have?

Some other questions:

Do you know the router's IP address and are your computers on the same subnet? (192.168.1.* or 192.168.2.* or 10.0.0.* etc.)

Can you ping the router from any of the PC's?

Can you reach the internet with "gateway"?

If you just want to use your router as a switch then plug the gateway into one of the LAN ports and do not use the WAN port.