Recortes de Ignacio Rodríguez de Rementería / @micronauta

2010/08/05

BGAN: video streaming from anywhere


Since the world was young and the Internet was an experiment, vía satellite has been synonymous with large events and budgets. Only big news companies were able to afford to transmit live from anywhere, anytime. Now we all can.

With the increasing presence of terrestrial microwave, fiber and mobile voice and data services, the exclusiveness of live coverage has diminished, but if I had been told just a few years ago that I could do live video from anywhere using a device the size of a laptop and for an accessible price I would not have easily believed it.

Let me stress the anywhere part, it's not an exaggeration. This is not the kind of "anywhere" that we are used to as in mobile phones, this is a valley in the desert or the top a mountain, hundreds of km offshore or even onboard an airplane.

So when Globalsat Latam offered me the chance to test their service I just couldn't resist.

Moore's Law has made it to Clarke's Belt*

Thanks to advancements in telecommunications hardware and software we can now use a repeater 35 thousand km away to transport a video stream, and since it's Internet technology there is no need to worry about feeding the downstream somewhere and re-encoding the video.

The setup was simple and similar to commonplace streaming using personal electronics: a camera, a portable computer and cloud services like UStream make it possible; the satellite link makes it possible from anywhere.

My test involved a Sony PDX10 DV camera in it's native 16:9 mode, linked through Firewire to an Apple MacBook Pro with OS X and the free version of UStream Producer. This program talks directly to a Ustream.tv user account, allowing real-time webcasts that can be watched by a practically unlimited audience on the web. The PDX10 generates very low noise images, something especially important when using low-bandwidth codecs.

Shared bandwidth

The lowest quality available UStream preset requires a 200 Kbps upstream. The Hughes 9201 provided by Globalsat can handle up to 492 Kbps in shared bandwidth mode (Using the Cisco GIST app on the iPhone I was able to measure about 400 Kbps of available bandwidth).

This mode worked fluidly, I saw no lost frames or other problems while monitoring the webcast through another computer connected via a 4 Mbps (downstream) ADSL. As expected, video was delayed by about 90 seconds in total.

During my test the BGAN behaved better than the typical 3G UMTS connections I have tried for webcasting. Even though 3G has higher potential bandwidth and less latency, upstream bandwidth is usually limited and the service tends to be highly oversold. The Inmarsat BGAN seems better managed.

Dedicated bandwidth

The Inmarsat BGAN also has dedicated bandwidth modes. I only tried the 176 Kbps service, it turned out to be insufficient for UStream but quite enough for Qik and twitcasting.tv, both are lower quality compared to UStream but are optimized for mobile network environments, which have similar overall latency and bandwidth restrictions to satellite-based services.

So if I had to pay for mission-critical webcasting using UStream I would probably need at least 256 Kbps of dedicated bandwidth. Unfortunately the UStream codec is CBR (constant bit rate) so I was not able to lower the bandwidth requirements by setting the camera to 8 or 4 frames per second.

The BGAN terminal and service can be setup through a Mac and Windows compatible Java-based administration tool. This software makes it easy to select the type of service and configure the terminal so it automatically connects in a certain mode when powering up.

Perhaps the most unique part of setting up a streaming video session using this technology is pointing the antenna in the right direction, towards the satellite. It was easy in this case knowing the general position of the satellite and the terminal's built-in LEDs.

I conclude that this can be done by any user with a reasonable level of technical skills, no need to be a rocket scientist at all.

We all can, but...

Even though anyone able to purchase a semi-pro camera and a MacBook can buy a BGAN terminal, the service is expensive enough to require a business model, approximately US$500 for a 2 hour broadcast is not cheap enough for your average citizen journalist. A small newspaper, radio station or similar organization takings steps towards the online landscape can afford it and use it to provide instant coverage of events when video quality is not a priority, but the 176 Kbps will not deliver commercial grade video with common codecs.

Availability

BGAN service and several compatible terminals can be purchased in Latin America through Globalsat Latam, there is more information available in this Wikipedia entry about BGAN.

* The "Clarke's Belt" is the ring around the planet where geosynchronous satellites are can be placed in orbit, more in Wikipedia.

I am involved in the design and content creation for an upcoming version of the Globalsat Latam website.
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