more ports on physical network

I have a Netgear RangeMax WNR854T (?) 1 gb router/wireless router. It has four physical ports, which I'm occasionally unplugging and replugging them, usually when clients are in the room needing to connect to the Internet. I'm thinking of adding an LTO tape backup device which would sit on the network as well, at which point I will ALWAYS need five ports at least.

I have had great luck with this router. I even bought an identical backup, because in my experience routers are the first things to fail (usually when you have a client in the room).

I'd like to have more physical ports for my network, and don't know how to go about it. Can I simply plug in a second router to one of the ports on this one? Would I be taking a major performance hit? If so, would that performance hit be confined to the devices that are connected to the secondary router, or to the whole network? Or, should I bite the bullet and buy a replacement for the router that I already have?

btw, it's a Mac/PC network and I have never had the time to go through everything and set that up properly (I have to reestablish the PCs on the Mac every time I boot up, and the PCs never see the Mac), but it works when I need it to.

Thanks!

Bob C

MacPro 2 x 3GHz dualcore; 10 GB 667MHz
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