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Although there's been no official information about the system used, it was almost certainly the ArcLight mobile broadband system from ViaSat, which also runs the Yonder in-flight Internet and data system. The company announced in July 2008 that a militarised, secure version for COTM (Communications On The Move) had been sold to the American Special Operations Command (USSOCOM) and had already been deployed in the Middle East, with rapid expansion promised. As the company said at the time,"This new operational capability [is] primarily for sending high resolution video back to higher command authorities for further analysis and identification". Data is relayed from terminals on the ground, in vehicles or in flight, to one of a number of satellites where ViaSat lease radio bandwidth, then sent on to an appropriate ground station where it's coupled into public networks.
The system is now fitted to American Black Hawk helicopters as used in the Bin Laden mission, most likely in the VMT-1220HE helicopter-specific configuration, as well as to 'several dozen' light MC-12 reconnaissance aircraft and multiple C-130 command and control aircraft. The C-130 fitting comes on a door, which replaces one of the aircraft's emergency exit hatches and can be swapped in or out swiftly.
ArcLight is used commercially to provide broadband to helicopters and private jets, Operating in the Ku band with a 14 GHz uplink and downlinks between 11 and 13 GHz, it can be configured in a number of ways, including 10Mbps down/512Kbps up or a symmetrical 3Mbps. The VMT-1220HE on the Black Hawk helicopters supports channel speeds of up to 5 Mbps to, and up to 325 kbps from the helicopter, which means President Obama probably didn't see the mission in HD, although with three aircraft bonding their uplinks together for close-on a megabit, it would have been possible.
With a 25 watt uplink via an 11.5 cm antenna and spread-spectrum modulation, coupled with a protocol designed to send packets in bursts, it's robust and forgiving of obstructions like helicopter blades, and will have good performance against jamming and other interference.
Although the published coverage maps for Yonder, which shares infrastructure with Arclight, show that the northern half of Pakistan is on the borders of an area not due to be covered until the third quarter of 2011, there are various ways that bandwidth can be provided out of published specification, including temporary movement of satellites, borrowing time from other operators and so on. ViaSat had expected to launch its own 130 Gbps satellite, ViaSat-1 early in 2011, but after the satellite was damaged during testing that launch has been put back to summer this year.
A great deal of security is built into the system. The American National Security Agency (NSA), which was involved in the mission, has built classified networks such as SIPRNet (Secret Internet Protocol Router Network) and JWICS (Joint Worldwide Intelligence Communications System) that the ArcLight COTM can connect to. Devices like ViaSat's AltaSec KG-250X provide encryption and other secure IP management features at up to 100Mbps full-duplex, so local wireless comms in a location can be turned into a secure enclave with full protection. This level of security is generically known as TS/SCI - Top Secret/Sensitive Compartmented Information, and is essential for highly sensitive government data on shared infrastructure public networks.
Using this sort of configuration, any portable streaming wireless webcam can be easily made part of the secure network, with megabit bandwidth back to anywhere in the world – including operations rooms in the White House.
zdnet.co.uk
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