Performance Testing

Before I go any further, just a warning that this is dense, and even for me there are an almost overwhelming number of tables. I struggled with how to present data and settled on the format below, which consists of individiaual tables and a few graphs at the end in case you're a visual person. There's a third option however, which is the google docs spreadsheet I used while collecting data. I've made it public for your enjoyment and it contains the exact same data. (Update: Google Apps is acting wonky and not letting me share the spreadsheet quite yet—it will be posted in a little while. Update 2: Here we go, finally got the link to the spreadsheet for your persual)

First up is the received signal strength, which will show just how much difference that extra ~140 mW will buy. In reality, it’s surprisingly hard to see the difference, but again that increase in strength is only a few dBm, so I suppose it not being very dramatic here is to be expected since this is also a logarithmic scale. That said, the Gen 5 does post numbers correspondingly above the Gen 4 on average; remember that closer to 0 is higher power and thus better. The difference is actually more visible on 2.4GHz than 5GHz based on these numbers.

agrCtlRSSI (dBm) Comparison—2.4GHz (Closer to 0 is Better)
  2011 MacBook Pro (BCM4331,3x3:3) 2010 MacBook Pro
(BCM4322,2x2:2)
Apple Airport Extreme 4th Gen 5th Gen 4th Gen 5th Gen
Office (1) -46 -44 -45 -40
Hallway (2) -52 -50 -52 -52
Downstairs (3) -71 -70 -77 -77
Kitchen (4) -84 -81 -85 -84

agrCtlRSSI (dBm) Comparison—5GHz (Closer to 0 is Better)
  2011 MacBook Pro (BCM4331,3x3:3) 2010 MacBook Pro
(BCM4322,2x2:2)
Apple Airport Extreme 4th Gen 5th Gen 4th Gen 5th Gen
Office (1) -47 -48 -44 -47
Hallway (2) -59 -60 -54 -52
Downstairs (3) -81 -81 -82 -81
Kitchen (4) N/A N/A N/A N/A

Next is MCS (Modulation Coding Scheme) which shows how fast the card is connecting to the 802.11n network. Here we can see how much the 5th generation airport extreme improves MCS selection in a number of cases, especially the three spatial stream scenarios on the 2011 MacBook Pro.

MCS Comparison—2.4GHz (Higher is Better)
  2011 MacBook Pro (BCM4331,3x3:3) 2010 MacBook Pro
(BCM4322,2x2:2)
Lenovo X300
(Intel 6300 3x3:3)
Apple Airport Extreme 4th Gen 5th Gen 4th Gen 5th Gen 4th Gen 5th Gen
Office (1) 22 23 14 15 23 23
Hallway (2) 11 22 13 15 22 22
Downstairs (3) 4 12 0 11 21 13
Kitchen (4) 0 8 0 9 5 12

MCS Comparison—5GHz (Higher is Better)
  2011 MacBook Pro (BCM4331,3x3:3) 2010 MacBook Pro
(BCM4322,2x2:2)
Lenovo X300
(Intel 6300 3x3:3)
Apple Airport Extreme 4th Gen 5th Gen 4th Gen 5th Gen 4th Gen 5th Gen
Office (1) 23 23 15 15 23 23
Hallway (2) 21 22 15 14 12 22
Downstairs (3) 1 9 1 2 5 5
Kitchen (4) N/A N/A N/A N/A 3 3

Locations 3 and 4, which are in challenging environments, see massive increases, previously going from the lowest possible (or not even 802.11n) rate up to much faster rates on both MacBooks.

AFS is our next test, where we transfer a 500MB zip file up and down from an AFS server and average the throughput. On the downstream side of things, the improvements aren’t substantial until we’re in a challenging RF scenario downstairs;, here the new generation wireless card in the Airport Extreme makes a huge difference in throughput on 2.4GHz, and similarly on 5GHz, though at the farthest location it’s still impossible to connect to 5GHz.

AFS File Transfer Performance (Downstream)—2.4GHz (Mbps—Higher is Better)
  2011 MacBook Pro (BCM4331,3x3:3) 2010 MacBook Pro
(BCM4322,2x2:2)
Apple Airport Extreme 4th Gen 5th Gen 4th Gen 5th Gen
Office (1) 97.3 96.8 64.2 76.6
Hallway (2) 85.5 90.5 65.3 71.8
Downstairs (3) 2.67 68.7 2.1 39.4
Kitchen (4) 1.34 33.6 N/A 16.5

AFS File Transfer Performance (Downstream)—5GHz (Mbps—Higher is Better)
  2011 MacBook Pro (BCM4331,3x3:3) 2010 MacBook Pro
(BCM4322,2x2:2)
Apple Airport Extreme 4th Gen 5th Gen 4th Gen 5th Gen
Office (1) 140.6 148.4 95.3 122.9
Hallway (2) 86.3 130.9 84.9 99.5
Downstairs (3) 16.1 39.3 6.6 19.5
Kitchen (4) N/A N/A N/A N/A

When it comes to upstream, the results are dramatic both on 2.4GHz and 5GHz. Throughput is almost always over double, thanks probably in part to the better front end and receive sensitivity of the Airport Extreme’s new wireless stack.

AFS File Transfer Performance (Upstream)—2.4GHz (Mbps—Higher is Better)
  2011 MacBook Pro (BCM4331,3x3:3) 2010 MacBook Pro
(BCM4322,2x2:2)
Apple Airport Extreme 4th Gen 5th Gen 4th Gen 5th Gen
Office (1) 54.0 128.6 52.6 81.5
Hallway (2) 45.3 105.1 30.9 78.1
Downstairs (3) 4.0 37.6 2.8 32.7
Kitchen (4) N/A 10.5 N/A 15.3

AFS File Transfer Performance (Upstream)—5GHz (Mbps—Higher is Better)
  2011 MacBook Pro (BCM4331,3x3:3) 2010 MacBook Pro
(BCM4322,2x2:2)
Apple Airport Extreme 4th Gen 5th Gen 4th Gen 5th Gen
Office (1) 186.7 214.5 150 134.2
Hallway (2) 175.2 195.8 145.7 119.5
Downstairs (3) 19.8 34.3 11.6 21.6
Kitchen (4) N/A N/A N/A N/A

Iperf is finally up, which we can run on the X300 in addition to both Macs. Here on downstream the results are improved pretty substantially for the 3x3:3 2011 MacBook Pro, and across the board for the challenging downstairs RF scenarios. The same applies on 5GHz as well, and in the best case, we can push nearly 300 Mbps on the new MacBook Pro. It’s a dramatic improvement in best case throughput if you have the right card, though the Intel card ends up performing similarly on 5GHz with both the new and old Airport Extreme card. More on that in a second.

iperf 2.0.5 (Downstream)—2.4GHz (Mbps—Higher is Better)
  2011 MacBook Pro (BCM4331,3x3:3) 2010 MacBook Pro
(BCM4322,2x2:2)
Lenovo X300
(Intel 6300 3x3:3)
Apple Airport Extreme 4th Gen 5th Gen 4th Gen 5th Gen 4th Gen 5th Gen
Office (1) 112 161 71.9 87.4 88.3 84.8
Hallway (2) 91.7 138 69.1 78.1 75.8 84.7
Downstairs (3) 5.89 117 2.22 46.9 51.9 68.7
Kitchen (4) 1.49 35.2 N/A 23.7 14.4 46.1

iperf 2.0.5 (Downstream)—5GHz (Mbps—Higher is Better)
  2011 MacBook Pro (BCM4331,3x3:3) 2010 MacBook Pro
(BCM4322,2x2:2)
Lenovo X300
(Intel 6300 3x3:3)
Apple Airport Extreme 4th Gen 5th Gen 4th Gen 5th Gen 4th Gen 5th Gen
Office (1) 213 311 92.2 136 101 112
Hallway (2) 119 243 95.4 97.2 98 106
Downstairs (3) 17.5 47.9 6.83 21.3 41.5 57.5
Kitchen (4) N/A N/A N/A N/A 13.8 11.1

On the upstream with Iperf things improve dramatically across the board on 2.4GHz, and marginally improve on 5GHz with the new WLAN card inside the Airport Extreme.

iperf 2.0.5 (Upstream)—2.4GHz (Mbps—Higher is Better)
  2011 MacBook Pro (BCM4331,3x3:3) 2010 MacBook Pro
(BCM4322,2x2:2)
Lenovo X300
(Intel 6300 3x3:3)
Apple Airport Extreme 4th Gen 5th Gen 4th Gen 5th Gen 4th Gen 5th Gen
Office (1) 57.7 159 64.2 97.7 65.1 126
Hallway (2) 33.1 120 24 98.4 42.3 113
Downstairs (3) 4.42 36.7 4.26 33.6 20.6 38.4
Kitchen (4) 1.89 11.6 1.50 8.51 7.39 21.1

iperf 2.0.5 (Upstream)—5GHz (Mbps—Higher is Better)
  2011 MacBook Pro (BCM4331,3x3:3) 2010 MacBook Pro
(BCM4322,2x2:2)
Lenovo X300
(Intel 6300 3x3:3)
Apple Airport Extreme 4th Gen 5th Gen 4th Gen 5th Gen 4th Gen 5th Gen
Office (1) 215 302 168 191 154 148
Hallway (2) 196 252 169 174 150 144
Downstairs (3) 15.4 41 7.97 22.9 26.8 39.4
Kitchen (4) N/A N/A N/A N/A 7.55 8.66

At the end of the day, the new Airport Extreme dramatically improves throughput in the best case and in a few regions where signal was previously unusable. In the worst case (location 4), performance improves from being essentially unusable to totally fine, and in the case of the 2010MBP goes from not being able to connect at all to pushing 23 Mbps.

So the unanswered question is how the 3x3:3 2011MBP manages to be much faster compared to the 3x3:3 Intel 6300 card, and I suspect the answer might be that the combination of BCM4331 on the client and BCM4331 on the AP enables Apple to use Broadcom’s frame bursting high speed modes—aka modern speedbooster. Careful observers will note in addition that while Iperf over 40 MHz 802.11n (with a link rate of 450 Mbps) delivers 311 Mbps of downstream, the same test on AFS is around 150 Mbps down, possibly due to compression. In addition, note how the Intel card lags behind in locations 1 and 2 until signal gets lower and then becomes competitive again. To me, this definitely seems to indicate some Broadcom-to-Broadcom enhancements are at play. Frankly for Apple this makes sense considering their top to bottom ecosystem control; if you have the ability to choose the card in the AP and the client, why not go with a solution that offers benefits?

Airport Extreme vs. Time Capsule

The next question is how the Time Capsule compares. Rather than re-run all 128 data-points (and then multiple tests per scenario for the purposes of averaging and removing outliers), I decided to use a subset and see whether performance and range is the same on the Time Capsule in those cases. As we showed before, the Time Capsule and Airport Extreme use the same exact wireless card, though gain is different on the Time Capsule antennas than the Airport Extreme.

For this testing, I just used the 2011MBP with its 3x3:3 radio, and ran through signal measurements and Iperf. First up is how signal strength looks.

agrCtlRSSI (dBm) Comparison (Closer to 0 is Better)
  2.4GHz 5GHz
  Airport Extreme Time Capsule Airport Extreme Time Capsule
Office (1) -44 -41 -48 -49
Hallway (2) -50 -51 -60 -60
Downstairs (3) -70 -68 -81 -83
Kitchen (4) -81 -81 N/A N/A

You can pretty much immediately tell that things are very similar. On 2.4GHz and 5GHz the two are very comparable except in a few odd cases. Of course the propagation isn’t going to be identical between the two, but subjectively it’s close.

Next is MCS, and here things are again close, with the Time Capsule narrowly edging out the Airport Extreme on 2.4GHz, and things being very equal on 5GHz. It’s looking the same so far.

MCS Comparison (Higher is Better)
  2.4GHz 5GHz
  Airport Extreme Time Capsule Airport Extreme Time Capsule
Office (1) 23 23 23 23
Hallway (2) 22 23 22 23
Downstairs (3) 12 13 9 8
Kitchen (4) 8 9 N/A N/A

So what about performance now with Iperf? On the downstream side of things, the Airport Extreme comes out on top narrowly in all but the second location on 2.4 and 5GHz. But the difference is minuscule.

iperf 2.0.5 (Downstream) (Mbps—Higher is Better)
  2.4GHz 5GHz
  Airport Extreme Time Capsule Airport Extreme Time Capsule
Office (1) 161 157 311 306
Hallway (2) 138 154 243 246
Downstairs (3) 117 103 47.9 44.9
Kitchen (4) 35.2 29.6 N/A N/A

Upstream is a similar story, with the two being very close outside locations 3 and 4, where the Time Capsule narrowly edges the Airport Extreme out on 2.4GHz.

iperf 2.0.5 (Upstream) (Mbps—Higher is Better)
  2.4GHz 5GHz
  Airport Extreme Time Capsule Airport Extreme Time Capsule
Office (1) 159 153 302 304
Hallway (2) 120 129 252 251
Downstairs (3) 36.7 55.5 41 32.1
Kitchen (4) 11.6 17.3 N/A N/A

All said and done however, the two are incredibly close and despite the difference in gain that the FCC docs would lead you to believe, are virtually indistinguishable in some real-world testing. In my mind, if you’re concerned about WiFi performance, the Time Capsule and Airport Extreme both perform equally well.

Graphs

If you're a more visual person and find that wall of tables and text too daunting, Anand also made some awesome graphs which I would be remiss to not reproduce here for your viewing pleasure.

First up is AFS performance compared on the 2011MBP between the 4th and 5th generation Airport Extreme.

 

Again the main improvements with AFS (real-world file transfer) happen out at the extremes where previously signal was unusable on 2.4GHz, and likewise on 5GHz. That really tells the story of the (sometimes dramatic) difference that the higher power WLAN solution in the 5th generation makes over the 4th generation.
 
Next are two charts showing again that for WiFi purposes the Time Capsule and Airport Extreme are virtually identical.

Within the margin of error, we see the Time Capsule and Airport Extreme perform very, very closely.

WiFi Testing Methodology Disk Performance - Airport Extreme vs. Time Capsule
POST A COMMENT

103 Comments

View All Comments

  • tipoo - Saturday, August 06, 2011 - link

    Are there any non-Apple routers using this new Broadcom wireless chip? Would they get the same performance with the same chip, or is there some added Apple-juice in there? No doubt this is a great router, just very pricey. Reply
  • tipoo - Saturday, August 06, 2011 - link

    Oi, I should read slower, heh

    "There’s a stigma that Apple gear is more expensive, and for the 3TB Time Capsule that may be the case, but the Airport Extreme is actually right near where it should be. Take for comparison the Linksys E4200, which is a 2x3:2 device on 2.4GHz, and 3x3:3 on 5GHz, and also Broadcom based. That device runs for $179.99 and features similar functionality including a USB 2.0 port for sharing devices. At $179.00, the Airport Extreme offers full 3x3:3 on both 2.4 and 5GHz, albeit the E4200 does have considerably more Tx power, which we'll investigate in a forthcoming article."
    Reply
  • lowlymarine - Saturday, August 06, 2011 - link

    Calling Caviar Green's "server grade" strikes me as galling even for Apple, who are pretty willing to play fast-and-loose with truth in advertising as it is. Reply
  • repoman27 - Saturday, August 06, 2011 - link

    This odd bit of nomenclature has been around and much debated since Apple first introduced the Time Capsule. WD Caviar Green drives generally offer the lowest price per GB combined with some of the best performance per watt for a 3.5" spinning disk on the market... Just ask Google how many they currently have deployed. So yes, they are ideal for servers.

    What isn't "server grade" in the Time Capsule is the utter lack of redundancy within the device itself. The intended usage model for the TC is as a backup device though, so there is redundancy in the overall system, i.e. you never actually store critical data on it, just a backup of critical data, therefore if it fails it's not much of a problem.
    Reply
  • solipsism - Saturday, August 06, 2011 - link

    Can the Linksys E4200's USB port be used for a printer the way the Time Capsule and AirPort Extreme/Express can? Reply
  • Brian Klug - Saturday, August 06, 2011 - link

    I know it can share attached USB Mass Storage devices, but I'm actually not certain about printers. Jarred probably will talk about it in his review soon.

    -Brian
    Reply
  • ThomasA - Saturday, August 06, 2011 - link

    Does the AE software offer a means to record data usage? With the 'new' DSL caps set by At&t I'd like to be able to compare my info on usage vs. theirs. Reply
  • Brian Klug - Saturday, August 06, 2011 - link

    You could watch the SNMP counters and use one of many software packages (including some big ones like MRTG/Cacti) but that's sort of daunting admittedly. There's nothing in airport utility that will show data use. That's just another thing I leave to Tomato on a WRT54G-TM personally.

    -Brian
    Reply
  • deadshort - Saturday, August 06, 2011 - link

    Here's a general suggestion for hardware reviews: could you plug the gizmo under examination into a power meter instead of just the wall and eyeball up some numbers? These days green geeks fret over these matters, especially for 365x24 devices like routers. The badge or spec. numbers are often worthless. Just a thought, thanks.

    Oh, nice review, BTW. I agree that the recent Apple 802.11 gear is getting boringly reliable and decent, in a good sense. You can't tweak the firewall in quite the gruesome detail I'd like, but the box never needs attention or unplanned restarts. The he.com tunnel works fine, the BSD/Roku/Apple/Sony/Epson clients are happy, there is no drama to upset the non-geeks. Not bad, even for the price.
    Reply
  • Brian Klug - Saturday, August 06, 2011 - link

    I actually completely forgot to mention my Kill-A-Watt numbers. I don't recall the Time Capsule numbers off the top of my head, I saw a peak power use of 11 watts on the Airport Extreme Gen 4 (while data was being transacted on 2.4 and 5 GHz) and 12 watts on the Gen 5.

    -Brian
    Reply

Log in

Don't have an account? Sign up now