Here I am, over the clouds again and an interesting aspect of flying in the US is that they have Internet access on board on many of their flights. Here's how it worked for me while putting together this blog post:
On Delta, Internet over the clouds is provided by GoGoAir and I was getting download speeds between 1 and 3 Mbit/s with round trip times of around 90 ms without my VPN. With an OpenVPN tunnel to my gateway in Europe I got round trip delay times of around 260 ms, quite a good value as well. In the uplink direction I got around half a megabit per second out of the connection. Over the hour I used the system it was quite stable but there were temporary outages of 15-20 seconds every now and then and occasional long round trip times of several seconds while data only trickled in. Not sure why these things happen, cell edge or handover problems perhaps?
Wikipedia says that the system uses 160 ground base stations distributed over the continent and 'classic' EvDo 3G connectivity between the plane and the ground. That would be consistent with the speeds I've experienced but it could of course always be that traffic shaping is applied on a device basis and overall speeds could have been higher.
Web browsing felt snappy and just for the fun of it I dropped my VPN tunnel for a little while to see if Gogo still forges Google certificates for Youtube. It looks like the bad press around the issue has made them think about it again and I couldn't observe rogue certificates for Youtube anymore.
Today a 3G link to the ground might still be sufficient but with rising data traffic the system needs to be upgraded to a faster technology in the future. Let's see if ground based LTE will be the technology of choice for planes flying over ground rather than satellites which are the only choice over oceans for obvious reasons. Personally I'd prefer ground based communication, as using satellites in geostationary orbit results in very long round tip delay times.
Actually LTE-based ATG networks are in the works.
Alcatel-Lucent and Inmarsat are working on an Europe-wide hybrid aviation network consisting of a ground network and a complementary space component (“Europasat” to be launched next year) which is set to share frequency spectrum with the earlier (presumably also for regulatory reasons as the spectrum is associated to orbital use):
http://www.satellitetoday.com/technology/2014/11/20/inmarsat-joins-forces-with-alcatel-lucent-for-eu-aviation-network/
in detail:
http://www.intelsat.com/wp-content/uploads/2014/10/In_flight_connectivity_takes_off.pdf
Given that Intel targets a bandwidth of 75 Mbps the air interface of the terrestrial component seems to be based on a single stream with 64QAM using the full 2*15 MHz block.
Inmarsat and Solaris Mobile (a JV between Eutelsat and Astra) each own 2*15 MHz in the 2-GHz-MSS bands (1980-2010 MHz paired with 2170-2200 MHz), so technically there is scope for competition based on a fully compatible technology.
As of North America last year AT&T first acquired 19 regional frequency licenses in the WCS band (2.3GHz) from Sprint and later announced to deploy an LTE-based ATG network to this band where they since have at least 2*10MHz nationwide. Weeks after that, however, plans were scrapped and Gogo was mulling to lease that very spectrum from AT&T:
http://www.runwaygirlnetwork.com/2014/11/13/gogo-happy-to-talk-att-spectrum-after-telco-bails-on-inflight-internet/
Unrelated to that Gogo is eyeing a chunk of up to 250MHz in the 14GHz band which may at some point be auctioned off:
http://www.fiercewireless.com/tech/story/qualcomm-gogo-continue-clash-over-flight-spectrum-rules/2015-02-16
As usual it is all about spectrum, but LTE will definitely make it into heaven.
Hopefully before end of the decade we will also see at least one out of the many LEO-HTS constellations to be launched which will solve the bandwidth and latency issues globally. With Honeywell signing an MoU with OneWeb the first IFC provider has teamed up with one of the LEO-HTS players recently:
http://baviation.cn/en/mro/all/engine-parts/4078-oneweb-selects-honeywell-as-a-key-partner-in-game-changing-effort-to-bring-high-speed-internet-to-billions-worldwide
For insights into the IFC market I recommend the following news site and the LinkedIn group founded by its chief editor, Mary Kirby:
http://www.runwaygirlnetwork.com/category/connectivity/
https://www.linkedin.com/grp/home?gid=4723000