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I had a chance to try out one of the new Sierra Wireless IntelliGo mobile Wi-Fi hotspots from Road Runner Mobile, today. The Wi-Fi hotspot is actually just a little router with WiMAX, CDMA (EV-DO), and Wi-Fi radios. The WiMAX radio represents one of the two so-called 4G cellular technologies, the other being LTE.

The Road Runner Mobile service provided by Time Warner Cable is actually Clearwire's WiMAX service, which falls back to Sprint's EV-DO network (3G) when WiMAX isn't available. It might fall back to 1xRTT, too, if 3G isn't available, but I had no easy way of testing this (well, without driving deep into South Carolina).

IntelliGo

To set the stage, I can currently get around 2.7Mbps (megabits per second) with 79ms of varying latency on AT&T's UMTS network on a very good day.

For testing, I used wget to this URL and ran MTR to dax.

I first tried powering up this thing in my condo, and after what seemed like over 90 seconds of staring at the bootup logo, it started up.. but on Sprint's EV-DO network (at 80% signal strength)! I ran my tests anyway, and peaked around 1.3Mbps but averaging around 640Kbps. Latency sucked:

HOST: six                         Loss%   Snt   Last   Avg  Best  Wrst StDev
  1. foobarz.lan                   0.0%     8    1.7   2.7   1.5  10.2   3.0
  2. 68.28.249.69                  0.0%     8  124.7 264.0 124.7 463.1 127.0
  3. 68.28.249.91                  0.0%     8  135.8 258.7 127.8 451.9 117.1
  4. 68.28.251.54                  0.0%     8  154.9 265.8 147.8 455.1 121.1
  5. 68.28.255.9                   0.0%     8  173.9 262.9 135.3 449.9 118.2
  6. ???                          100.0     8    0.0   0.0   0.0   0.0   0.0
  7. 68.28.253.69                  0.0%     8  134.1 236.0 124.6 419.1 107.7
  8. sl-crs3-fw-0-1-3-0.sprintlin  0.0%     8  169.0 229.2 122.0 383.1  85.1
  9. sl-crs1-fw-0-7-0-0.sprintlin  0.0%     8  141.2 228.7 125.8 379.7 101.2
 10. sl-st21-dal-1-0-0.sprintlink  0.0%     8  128.4 236.8 128.4 377.6  94.6
 11. dls-bb1-link.telia.net        0.0%     8  132.3 214.7 129.1 319.1  72.3
 12. atl-bb1-link.telia.net        0.0%     8  229.4 256.4 170.0 447.0  87.0
 13. ash-bb1-link.telia.net        0.0%     8  240.5 272.1 173.7 449.7 109.7
 14. voxel-ic-129445-ash-bb1.c.te 12.5%     8  192.0 259.2 167.7 418.9 104.3
 15. 0.te6-2.tsr1.ewr1.us.voxel.n 12.5%     8  176.8 276.4 165.7 525.4 124.9
 16. 842.te1-7.csr2.lga6.us.voxel 12.5%     8  168.0 297.1 168.0 607.8 145.9
 17. dax.prolixium.com            12.5%     8  203.5 277.2 181.6 558.1 132.8

I had to toggle the option in the web interface to force the unit to only use 4G service. Only after I did this, it barely got a WiMAX signal and got me online. The web interface indicated I had poor signal strength at -88dBm (it rated this at 10% - I guess this is why it automatically picked 3G initially), and I agreed. I could only get roughly 360Kbps and the latency was all over the place:

HOST: six                         Loss%   Snt   Last   Avg  Best  Wrst StDev
  1. foobarz.lan                   0.0%     8    1.6   2.1   1.6   3.1   0.5
  2. 71-23-64-2.clt.clearwire-wmx 12.5%     8  276.1 190.1  87.4 485.0 144.0
  3. 71-22-7-161.clt.clearwire-wm  0.0%     8  211.2 289.6 111.3 703.8 216.9
  4. 66-192-62-1.static.twtelecom 12.5%     8   85.4 316.1  85.4 673.8 225.5
  5. ash1-pr1-ge-2-0-0-1.us.twtel  0.0%     8  265.2 266.7  95.9 574.1 183.7
  6. 0.te6-2.tsr1.ewr1.us.voxel.n  0.0%     8  155.2 231.1  81.1 474.5 126.4
  7. 842.te1-7.csr2.lga6.us.voxel  0.0%     8  125.2 200.7 125.2 374.8  79.8
  8. dax.prolixium.com             0.0%     8  124.6 167.3  98.2 297.7  76.1

DNS is slightly intercepted on the IntelliGo, since the PTR record for 192.168.0.1 was translated to $my_ssid.lan. No, foobarz is not my real SSID.

After driving around Ballantyne a little bit, I managed to figure out which tower was providing the WiMAX coverage for the area. It ended up being the one near Toringdon that's easily seen from I-485. I got the signal strength up to -47dBm (80%) by sitting in a parking lot of one of the office buildings in the area:

WiMAX Tower

I could have gotten closer by walking across the grass, but I figured the orientation of the antennas would result in worse signal strength as I got closer. Oh, maybe I was just lazy.

I managed to peak at 6.76Mbps down, while the transfer rate typically hovered around 5.5Mbps. Latency was a little better, too:

HOST: six                         Loss%   Snt   Last   Avg  Best  Wrst StDev
  1. foobarz.lan                   0.0%     8    1.7   6.0   1.7  18.2   7.3
  2. 71-23-64-2.clt.clearwire-wmx  0.0%     8   66.1  78.1  65.3  94.4  12.4
  3. 71-22-7-161.clt.clearwire-wm  0.0%     8   76.0  77.1  61.1  97.6  12.2
  4. 66-192-62-1.static.twtelecom 12.5%     8   65.8  69.7  50.9  92.2  12.1
  5. ash1-pr1-ge-2-0-0-1.us.twtel  0.0%     8   80.7  84.3  79.8  97.2   5.5
  6. 0.te6-2.tsr1.ewr1.us.voxel.n  0.0%     8   85.6  90.7  74.8 107.6  10.0
  7. 842.te1-7.csr2.lga6.us.voxel 12.5%     8   60.7  82.5  60.7 102.9  17.0
  8. dax.prolixium.com             0.0%     8   86.5  92.7  82.1 105.9   9.9

Although not shown above, I managed to get one response back from the second hop (the other end of the PPP connection, no doubt) in 40ms. Supposedly LTE's RTT is in the 30s, so this certainly comes close!

Stopping at different points around Ballantyne with an average of around -57dBm got me between 3-4Mbps. Not too bad, but not that big of a jump over AT&T in the middle of the night (ie, no iPhone users).

The IntelliGo device itself is slightly disappointing. Battery life on the unit dropped to around 50% after 50 minutes of moderate use. The startup time before even starting the initialization of the radios is way too long (I mentioned 90 seconds earlier, but it could have been longer). Also, I don't know if it's just a result of the high frequency used by WiMAX (>2GHz) compared to other mobile networks or a problem with the IntelliGo itself, but I was disconnected left & right when driving and moving around. The kicker was hearing a beep (it makes certain noises for connecting & disconnecting from the mobile network, and when clients connect) consistently when I drove under overpasses!

In conclusion, I probably wouldn't buy one of these, but I don't travel too much, either. It's probably great for Internet access at airports and other public places where Wi-Fi is either not free or terribly congested.. as long as you've got WiMAX coverage, which doesn't seem to be too widespread, yet. Sprint's 3G isn't too shabby, though, but still pales in comparison to the speeds and latency of AT&T's UMTS network, even when congested with iPhones.