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My title asks it all. How the connection for this remote warfare works with a absolutely low network latency (which i believe is essential to achieve a remotely possible war experience) even after it passes through optics till Europe and then satellites to Afghan or Iraq?

Now, is this a valid SF question? You decide.

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closed as off topic by Jim B, Massimo, Chopper3, Zypher, Mark Henderson May 24 '10 at 22:30

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An interesting and great question, but sadly off-topic, especially as I don't think the army is going to give away their military secrets to feed our curiosity ;) –  Mark Henderson May 24 '10 at 22:30
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2 Answers 2

Wildly off-topic but the answer is simpler than you think.

Basically they're not 'flying' them for 99% of the mission, they're semi-autonimous. They're really only tasked with two types of role; fly to a position and fly a set path - i.e. move and patrol. Entering and exiting an area-of-interest is a move, circling is a patrol - neither operation requires any user input once tasked. Assisted takeoff and landing are often handled semi-manually but these operations can easily survive the ~1-1.5-second round-trip latency typically seen.

You're right about latency ruining any chance of manual target acquisition or unscripted counter-attack but these functions are again typically automated/semi-automated. When a driving team commits to a deployment there can often be a delay of tens-of-seconds in which the platform goes through its acquisition/release/track process chain - none of which needs any user input post commit. There are often scripted threat-avoidance procedures in place and threats are usually known about with >30-seconds notice, allowing the driving team to choose to leave the platform to manage itself out of the situation or to take other options. Be aware of course that the expected threat-survival rate for UAS is lower than that of regular aircraft.

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There probably isn't as much latency as you think. Remember it's the military. It's probably one hop to the satellite, and one hop back down to the drone, and military satellites tend to be in reasonably low orbits, so you wouldn't even have the light-speed latency of a trip to the Lagrange points (Or HEO) and back.

Edit: How do you figure 26,000 miles? You're assuming the satellites are in MEO, which isn't a valid assumption. Also light travels 26,000 miles in like .13 seconds, so even if it was traveling that far .5 second latency is about twice what you'd be seeing.

You're looking at the whole thing backwards. We know they're doing it. The question is how? My thought is that it's perfectly possible that they're bouncing off a series of LEO satellites, or that they're taking a fibre hop to Europe and bouncing a satellite from there.

Or alternately, they're flying with much greater latency than you'd think. It's not like they're dog fighting at high speeds or anything.

Edit2: Lot of people are talking about switching latency, and that's really only a factor in two cases:

  1. The switch is over utilized

  2. There are too many switches in the circuit

In this case, I would be very surprised if the latency was appreciably increased by the switches. It's far more likely that latency would be increased by encryption overhead or actual light-speed restrictions than by switching hardware.

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Geo-stationary orbit is much closer to Earth than the Lagrange points (three in lunar orbit, one just slightly closer than lunar orbit, one noticeably further than lunar orbit). –  Vatine May 24 '10 at 14:17
    
If you bounce a signal off a satellite in geosynchronous orbit, it is a minimum of about 26,000 miles in each of four hops, giving an absolute minimum latency of a bit over half a second. The closest I get to remote warfare, World of Warcraft, would be difficult to play with that latency, and I suspect real-life warfare is more demanding than an MMORPG. –  David Thornley May 24 '10 at 14:23
    
If you read the article it tells you exactly how they do it. A fiber link to Europe and satellite control from there as @Satanicpuppy theorizes –  Zypher May 24 '10 at 14:50
    
@Zypher Yep, I read that and even mentioned in my question. But even optics should have a considerable latency i believe eventhough it's not the home broadband connection –  blntechie May 24 '10 at 15:06
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