well there are limits on the length of runs before you need to add a switch. back when I made CAT5 twisted-pair copper runs by hand, 100 meters was the limit. not sure if that has changed with CAT6
I think reddit might disagree with you on that last part...
WPA was designed as an intermediate standard which would function on WEP-only hardware. That's why WPA uses TKIP instead of AES (which is what WPA2 uses). The devices may require firmware updates (which, of course, may not exist or may no longer be available) but the hardware itself is capable of WPA.
tell that to my Linksys WCG200. there are no firmware updates to give it WPA, though it is 802.11g. I have the original two-antenna model, and bought it myself, so my cable company has no claim on it. I really like the design, but there are very few all-in-one solutions for cable broadband, and none use 802.11n yet, so I am finding it hard to justify upgrading.
The meta-Turing test counts a thing as intelligent if it seeks to devise and apply Turing tests to objects of its own creation. -- Lew Mammel, Jr.