Thread: 802.11n or 802.11ac

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    802.11n or 802.11ac

    Guys, can you help me understand this:

    "How 802.11ac worksYears ago, 802.11n introduced some exciting technologies that brought massive speed boosts over 802.11b and g. 802.11ac does something similar compared with 802.11n. For example, whereas 802.11n had support for four spatial streams (4×4 MIMO) and a channel width of 40MHz, 802.11ac can utilize eight spatial streams and has channels up to 80MHz wide — which can then be combined to make 160MHz channels. Even if everything else remained the same (and it doesn’t), this means 802.11ac has 8x160MHz of spectral bandwidth to play with, vs. 4x40MHz — a huge difference that allows it to squeeze vast amounts of data across the airwaves."

    Source: What is 802.11ac WiFi, and how much faster than 802.11n is it? | ExtremeTech

    I'm sorry to bother you but I'm kinda slow with this stuff. I'm trying to choose between 802.11n or 802.11ac. My first choice is the ac thing because it was recommended by a computer sales agent. However, I think it will be cheaper to get the 802.11n. Can you tell me if these two do not have any big difference in terms of speed? Thanks.

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    I'm interested in what others have to say about this, too. Just my personal opinion:

    It's not just about speed, either; I've had connectivity issues, too. Where I live, the 2.4GHz band is pretty full, and congestion at peak times slows down the networking speed quite a bit. The 5 GHz band, on the other hand, is not nearly as congested (yet; it's about 10:1 ratio of base stations on the two bands), so in my case, the selection would depend on whether the 802.11n one supports the 5 GHz band or not.

    Since sales-speak is often full of lies and omissions, I'd definitely go for 802.11ac, just in case.

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    "You want the true-true?" Neither. Unless you enjoy random disconnects or are using this for home theater type of thing and don't care since the stream is low enough for you to force the hardware to cough. For any other type of home networking where speed must match with reliability, go wired and stick to intel chips.

    Maybe when Intel gets in with their own boards on the 802.11ac standard, you may experience an improvement, but so far all I have been told is these things aren't nowhere near ready for even mid-duty networking the likes which you would expect at your home. Much less in an office.

    Frankly, I have already lost my faith in wireless. Used to be a huge thing for me. So I'm being a tad biased because of that. But the new standard is an improvement on all aspects over the old one. You just won't find the equipment that can offer your reliability at big speeds yet. Stick to the old one and wait sometime around mid 2016 for an Intel solution. If they screw it too, then you know its hopeless. It always is...
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    Reimplementing a large system in another language to get a 25% performance boost is nonsense. It would be cheaper to just get a computer which is 25% faster.

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    Mario is 100% right. People tend to see the advertised max throughput on wireless and take that as gospel. I've got full signal strength from my office's 11n router and am supposedly connected at 130 Mbps, but transferring a file is a slow 3Mbytes/s (24 Mbps). Using the gigabit wired gives 34 Mbytes/s, full 12.5 Mbytes/s on 100Mbps wired. Just an example here, but I see the same sort of performance at home and have seen it at other places.

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    Me agrees too, wrt. wired vs wireless. Whenever I'm on AC power, I'm also using a wired ethernet, too. All my non-laptop/tablets have permanent wired connections. I definitely would not rely on wireless alone.

    Having wireless connectivity at home for tablets and such is nice, though, and I definitely prefer '.11ac over '.11n (due to preferring the 5GHz band).

    (When wiring a house or an apartment, I'd also prefer Cat7 SF/UTP cabling, or F/UTP at minimum; SF/FTP is probably overkill. (I don't like the idea of plain UTP parallel next to my electric wires.) 1GHz capable Cat7 if possible, but I'd be happy enough with 900 MHz, too. And a small patch panel somewhere. Very useful stuff, not just for ethernet, and it does not cost that much fully installed, either.)

  6. #6
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    Quote Originally Posted by Epy View Post
    Mario is 100% right. People tend to see the advertised max throughput on wireless and take that as gospel. I've got full signal strength from my office's 11n router and am supposedly connected at 130 Mbps, but transferring a file is a slow 3Mbytes/s (24 Mbps). Using the gigabit wired gives 34 Mbytes/s, full 12.5 Mbytes/s on 100Mbps wired. Just an example here, but I see the same sort of performance at home and have seen it at other places.
    Likely because you're using the 2.4 GHz band in a congested area (which is pretty much everywhere today).

    I've learned that when using the 2.4 GHz band, you should expect slow speeds and random disconnects. No way around it. Too much interference.
    Fortunately, it's not quite as bad with the 5 GHz band. You will cut through interference and get solid speeds with little to no disconnects. 5 GHz signals are much weaker, so signals propagate less distance and have trouble penetrating walls, so you need to ensure you're sufficiently near the router.

    Regardless, wireless is hard, so you need a good router and a good receiver. I did a test once. I got 30 mbps with the notebook's built-in wireless adapter and 150 mbps with external adapter (802.11n). So you need good equipment.
    If you find that the 5 GHz signals are too weak, consider investing in 802.11ac or wireless extenders. Never tried any of those, though.

    Regardless, you should consider wired connections. They just work. They're faster and cheaper too.
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    So, interesting follow-up to this: somehow the wireless N on the Xbox 360 seems to work better than wired 100.... and I don't have a performance router or anything. Claimed wifi speed according to the 360 is 65 mbps. Weird machine

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