Gogo a no go on VoIP

I was very excited when I got to the airport and saw that AirTran offered in-flight WiFi.  Who knew you could get WiFi on a flight from San Francisco to Milwaukee?  I’ve been dying to try VoIP over the Gogo Inflight Internet Service for some time now.Gogo

For $12.95, you get Gogo’s “unlmited” Internet access while in flight (it’s $9.95 for flights shorter than 3 hours, and a monthly all-you-can-eat pass goes for $49.95)). The prices are not bad — my dog is stuffed under the seat in front of me as I write this, and she had to pay $60 for that privilege.

You register once and can use multiple devices, so I was able to switch between my laptop and my iPhone.

Gogo’s terms of service explicitly prohibit the use of VoIP in mid air, but who reads the terms of service anyway. Besides, Oprah made a Skype call on Gogo on Virgin Air last month, and the company milked that marketing gimmick for all it was worth..

I ran some speed tests, the results look usable for VoIP:

VoIP test statistics
Jitter: you –> server: 3.2 ms
Jitter: server –> you: 6.0 ms
Packet loss: you –> server: 2.6 %
Packet loss: server –> you: 0.1 %
Packet discards: 0.0 %
Packets out of order: 0.0 %
Estimated MOS score: 3.7

Speed test statistics
Download speed: 698376 bps
Upload speed: 219640 bps
Download quality of service: 76 %
Upload quality of service: — %
Download test type: socket
Upload test type: HTTP
Maximum TCP delay: 631 ms
Average download pause: 23 ms
Minimum round trip time to server: 100 ms
Average round trip time to server: 111 ms
Estimated download bandwidth: 2240000bps
Route concurrency: 3.2074413
Download TCP forced idle: 0 %
Maximum route speed: 5242800bps

My first test was regular text chat, both XMPP and Skype work fine, with no noticeable transmission lag between messages. I was less lucky with video as an iChat video connection would error out after a few seconds.

Next I tried a Skype call, each side had perfect sound for the first three seconds, then the audio became garbled beyond recognition.

Then I tried RF Dial on my iPhone, again perfect audio for the first three seconds, then it became garbled and chopped.

I suspect Gogo is deliberately messing with the traffic.  Aircell, Gogo’s parent company, promotes VoIP calling as a key feature of its charter and general aviation offering.

Perhaps running the call through a VPN would produce better results? I would try it, but we have begun our decent into Milwaukee.  The test will have to wait until my return flight on the 29th.