Instruction: Answer the given question by extracting information from the supporting document.

Input:
Question: What is the difference between this rt-ac56u and the rt-ac56r?
Document: The signal is now stronger than the 2.4Ghz signal of the E3000. I routinely receive full to half bars on my Ipad on the 5GHZ spectrum in my bedroom where I had none before. This means that I will not have to put money on the AC68U which I suspect will cost at least $50 more for the external antennas. Unless you have a gigantic house, there's no need to get its big brother. As far as I know, the only difference between this and the AC68U are the external antennas and the extra stream radio that requires an equivalent adapter to use.
In fact, there was virtually no difference from plugging the internet modem directly to a desktop as I consistently got 28xMbps download speed through the RT-AC56U.- Much better network transfer speed too with my 2.5" 500MB external drive plugged into the router's USB port. Note that it is a USB 2.0 disk drive so I couldn't say whether a USB 3.0 one will affect the Wi-Fi speed.- On my Samsung Note 3 which supports 802.11ac, I am able to get blazingly fast Wi-Fi speed on 5GHz (fastest to date 257Mbps d/l & consistently in hundreds).
Currently, only the router Admin account and password can be used to access that interface(or app) and to see the files and network devices. I wanted to have my friends be able to log in and download files, like my Server 2012 Essential remote web access page works) but giving out the router admin account and giving them full access to everything and other network devices...sorry, no.This AC56U works great on my CenturyLink 50/20 DSL. I have the isp modem(Actiontec C1000a) in bridge mode and have the AC56u as my main router.
ok so the good its got great range, on both 2.4ghz and 5ghz channels, i have run into a issue where every once in a blue moon i cant pull up internet on the 2.4ghz band it says im connected and have internet but nothing will pull up till i turn off and back on the laptops wireless card. not sure why but its happened 2 times so far. and the easy fix is to turn the switch off and back on my laptop, the 5ghz channel works like a champ no issues there.
if you are thinking about picking up a cheaper AC router don't hesitate to buy this one,  it is so fast compared to my older N router i replaced,  I stream 1080p movies to 4+ devices at once now and never have a problem with buffering. the range is fantastic i have full bars throughout my entire 2000sqft house and the yard too.just make sure you update the firmware as soon as you plug it in! !
full range no matter the wall, easy to used and configurate look whel stable, and fast all i need in this product
cool,,,,,, great!I think u already check this router's spec!as same as the others comment!any question? its awesome. ^^
You will not regret getting this router. Faster response from any router i ever had. Simple and clean interface. range is pretty much the same though but it's Extreme reliable! !
Yes, the router does come with its own DLNA and download software, but it's not good. I will be looking to replace download master with transmission when I have time.This unit is basically the fastest consumer router on the market so far with full unlocked dual core and 256MB RAM. If it ever offers software package installs like the NAS units currently do, it could finally usher in the hybrid Router/NAS market. Do it, Asus!I will update this review with issues and its reliability later as I continue to use it.
Works good on the 5ghz band, but the 2.4ghz is disappointing for devices that limited to wireless N standard. Using the 2.4ghz band, it normally connects at 5mps....VERY DISAPPOINTING ! !
Answer: No hardware difference, just where it was bought from. U = online merchants, R = retail brick and mortar like bestbuy.