The Joys of 802.11ac WiFi
by Jarred Walton on July 8, 2013 8:15 PM ESTClosing Thoughts (for Now)
It’s really up to the notebook manufacturers to make sure that their WiFi implementations are up to snuff, and that means doing more than a quick test for connectivity in ideal test conditions. The QA and engineering departments at the very least ought to be testing at 5, 25, 50, and 100 feet, using standard Windows operations (i.e. not just IxChariot or iPerf). If there are issues, they should be ironed out before customers (and reviewers) get the product. With that said, a good foundation for wireless networking can go a long way toward improving bandwidth and stability of your connection.
Intel’s adapters aren’t always the best, but they’re rarely the worst, provided you get one of the non-budget offerings (i.e. avoid the 1000 and 2000 series parts). Realtek unfortunately comes in near the bottom of my ranking list in many cases, but most notebooks with Realtek WiFi are already cutting corners—they’re the 1x1:1 2.4GHz only solutions that are so common. The fact is, whether you're using an adapter from Qualcomm/Atheros, Broadcom, Marvell, Realtek, or Ralink, you can have a good adapter in some cases or a downright awful one in others. Broadly speaking, most solutions with two streams end up being better than any of the single stream solutions.
Of course, it's not just about spatial streams. Oddly enough, for a company that has been on the forefront of wireless technologies, as Anand detailed in our MacBook Air 2013 review OS X is not scaling TCP window size beyond 64KB and thus fails to get optimal performance out of 802.11ac. (I assume an OS/driver patch will address this at some point, but that hasn't happened yet AFAIK.) OS and driver issues can definitely put a clamp on WiFi performance, which again is why the notebook makers need to exercise due diligence and test in real-world scenarios to ensure their hardware is working properly.
As I said earlier, one of the best things about 802.11ac wireless is that it raises the bar for wireless adapters. No one can get away with selling you an 11ac adapter without including at the bare minimum a dual-band chipset with support for 5GHz and 2.4GHz networks. If you live in a packed subdivision or apartment complex, 5GHz networking is almost required these days. Ideally, though, I want more than just the bare minimum; I want two 80MHz streams on my 802.11ac connections, and three would be even better. Intel’s 7260 provides two streams, and so do most of the current crop of 802.11ac routers. Hopefully, we won’t see as many solutions going for the bottom of the barrel single stream implementations; they’re not worse than 802.11n, but they’re not much better than two stream 5GHz 802.11n either.
Consider this a warning shot across the bow of the notebook manufacturers: we’re going to be paying more attention to your wireless implementations going forward. I can understand why a $500 or less budget laptop needs to cut every corner possible to hit that price point, but when we’re looking at $1000+ laptops we don’t want to see such blemishes. It may not always be as painful as using a bad LCD on an otherwise excellent laptop, but a bad WiFi implementation that loses connectivity if you’re more than 40 feet from the router in can be even worse in some cases.
We’ll be doing some full reviews of 802.11ac routers in the near future, including the Western Digital AC1300 and Linksys AC1200. The full reviews will better characterize performance as well as other features. Until then, at least right now it looks like most 802.11ac routers are using two streams (867Mbps maximum theoretical throughput), which is at least a nice upgrade over the 300Mbps so many 802.11n routers offer. Meanwhile, Apple's latest AirPort Extreme and Time Capsule go whole hog and give us three streams and up to 1300Mbps. Now if I could just get (Windows) laptops with three 802.11ac streams, I might actually be willing to give up my Gigabit Ethernet and wires!
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HammerStrike - Tuesday, July 9, 2013 - link
Can anyone confirm if legacy standards (n/g/b/a) can be connected to a 801.11ac router, and still have it connect at ac speeds to ac native devices? I know that (at least with my current n class wifi router) if I connect a g class device the whole network goes down to g level speeds for all connected devices. Presumably with both 2.4ghz and 5ghz radio's the 2.4ghz can service legacy devices, while the 5ghz would be dedicated to ac devices. Is that correct, or and I misunderstanding that? Also, if I am correct, is that part of the ac standard, or up each manufacture to implement?name99 - Tuesday, July 9, 2013 - link
(a) Yes, the intelligent thing would be to segregate legacy devices to 2.4 GHz. Always has been.(b) With 802.11n, the smart thing to do is put the device in Greenfield mode for the 5GHz band, which will will not allow connections from anything except n.
(c) With 802.11ac, for better or worse there is no greenfield mode (maybe because pretty much no-one ever used it to run their networks optimally; Apple makes its use easy on Airport, but even there few people use it; apart from Apple no-one seems to even know it exists. You could maybe implement a greenfield mode equivalent in the router, just not allowing anyone not using ac to connect, perhaps by only broadcasting the SSID in 802.11ac format, but I don't know if that's within spec, or if anyone is doing it.)
This makes it even more imperative to get slow devices onto 2.4GHz, otherwise all your time is going to be used up by them slowly dribbling out their bits.
Gabik123 - Tuesday, July 9, 2013 - link
Can't wait for my almond+...hrrmph - Tuesday, July 9, 2013 - link
Good job putting the notebook computer manufacturers on notice that the performance of their wireless implementations are going to be measured (and how well they do counts a lot towards customer, and reviewer, satisfaction).They definitely need to get it right - especially on the expensive computers.
With form factors shrinking, the day when there isn't room for a LAN port is fast approaching, even for high-end machines.
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wrong - Tuesday, July 9, 2013 - link
Thanks for the roundup. It's good to see data on this underserved topic.The big question for me is still "wireless or copper?", though, so I found myself wanting two things:
* Stats for just running a patch cable to the test locations
* More information about those outliers. It's a llittle disconcerting to see pauses and disconnects pruned from the data when they are actually the biggest influence on the quality of your experience.
JarredWalton - Tuesday, July 9, 2013 - link
The pauses are usually on the first run -- sometimes Windows still hasn't figured out where the other PC is on the network when I switch from 2.4 to 5GHz, or wired to wireless. It's maddening, but there are many times when I power up a laptop, open the path to my main PC in Explorer (\Nehalem if you're curious -- yup, my work system is still running a Bloomfield CPU!), and then... wait, get told the system isn't online, ping the IP address and get a response, try again, etc. and then about five minutes later Windows finally figures out where \Nehalem is "hiding". Grrr.... Mind you, this is with all the Windows Firewall stuff disabled as well.Wintek - Tuesday, July 9, 2013 - link
JarredThanks for the review. I did want to share that the only things that matter to me are reliability and range. The definition of a positive experience for me is when my wife wants to use the facebook app on her iphone 5, and it works. I have a 15/5 Mbps internet connection, which means that the speeds of nearly every test case presented would result in the same experience for my wife - what I really want to know is if the device is going to require constant rebooting and if it's going to work out on the deck, which is ~75 feet away through 3 walls. I didn't even set up the 5GHz SSID in her phone because it can't even reach past the same room as the access point. As far as speed tests go, the test that would be useful to me is reporting the number of feet when the connection drops below a 15Mbps reliable transfer speed. I purchased a Western Digital My Net N900 router because of the 7 ethernet ports and reported speed to hard drives attached to the USB port. What a bad choice, none of the online reviews reported the failures (should have listened to the Newegg user reviews) of this device for what I am guessing is overheating. Initially I was very pleased with the device with 5 of the ethernet ports used and reasonable wireless 2.4GHz range. But the first two each died after ~3weeks. I then bought a Netgear switch and just used the router as an access point. So far the third WD router is still working, but I had to reset it last night because of slow/flaky connectivity. It's this kind of experience that I would love your help in avoiding!
andrewaggb - Thursday, July 11, 2013 - link
Totally with you. Reliability and range trump speed.whyso - Tuesday, July 9, 2013 - link
Honestly one of the few things I honestly couldn't care less about on my 5mbps internet connection. No company offers faster internet in my location though the population demand is there and I don't expect faster than 20mbps in the next five years.designerfx - Wednesday, July 10, 2013 - link
maybe you should test this with the Asus RT-AC66U? I imagine the results would be profoundly different, based on smallnetbuilder's test results.http://www.smallnetbuilder.com/wireless/wireless-r...