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2MBps Bandwidth Anywhere Via Suitcase Transmitter
mysticbob writes: "This newly announced suitcase satellite xmtr does 2MBps
upstream, anywhere in the world, and sounds easy to use.
Could be useful (someday) for lots of remote users. Of course,
it does require your ISP have a satellite NAP ... " This looks similar to (but sleeker than) another satellite video connection box we featured a little while ago, but without a built-in monitor. How small will these be in 5 years?
The Military has actually been using something like these for years (not exactly 2Mbps however). Our unit had something similiar, the idea being was to broadcast live video feed from special extremely lightweight cameras attached to our helmet, waist, and back.
We each had our own transmitter to carry the data to anywhere in the world.
I live under the bridge, in a pile of feces.
Thought wow 2 MBytes. That is a whole lot of bandwidth out of an item that small...It is 2 Mbit per second.
Oh well, tone down excitement. Bad editor, bad, bad editor, got me all excited.
That pesky speed of light is just too slow.
Best Slashdot Co
The company
The Press Release
The SWE-DISH site (requires flash) Also has a PDF of the specs for this boxes.
From the specs:
Encodes live Windows MEdia, Mpeg 4, Real Media and Mpeg 2.
Also has e-mail, ftp, internet as well.
There is a very interesting article about TCP that has more details on this. It's worth reading the whole article.
For those who don't have time/patience to read the full article, here's the most relevant part:
"Satellite-based services pose a set of unique issues to the network designer. Most notably, these issues include delay, bit errors, and bandwidth.
When using a satellite path, there is an inherent delay in the delivery of a packet due to signal propagation times related to the altitude of communications satellites. Geo-stationary orbit spacecraft are located at an altitude of some 36,000 km, and the propagation time for a signal to pass from an earth station directly below the satellite to the satellite and back is 239.6 ms. If the earth station is located at the edge of the satellite view area, this propagation time extends to 279.0 ms. In terms of a round trip that uses the satellite path in both directions, the RTT of a satellite hop is between 480 and 560 ms.
The strength of a radio signal falls in proportion to the square of the distance traveled. For a satellite link, the signal propagation distance is large, so the signal becomes weak before reaching its destination, resulting in a poor signal-to-noise ratio. Typical BERs for a satellite link today are on the order of 1 error per 10 million bits (1 ¥ 10-7). Forward error correction (FEC) coding can be added to satellite services to reduce this error rate, at the cost of some reduction in available bandwidth and an increase in latency due to the coding delay. "
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Roses are #FF0000, Violets are #0000FF, find / -name '*base*' |xargs chown -R us && mv zig greatjustice
I see people talking about how incredibly expensive this must be, as well as saying things like "Now we can get internet in the congo".
Let me enlighten you a bit.
You can already get internet just about anywhere via satellite. Yes, it will require a fixed installation and a hefty dish, but it's commercially available, NOT rediculously expensive (comparable to landline), and works quite well, all things considered.
Yes, the latency is high, thanks to the laws of the universe and all that... but if your choice is no internet, or 2Mbps with a 450ms latency tacked on off the bat, the 2Mbps will do fine. (it only really sucks for gaming anyway.. websurfing is fine)
The benefits of this portable, small unit are just that. It's portable, and it's small. It's not a breakthrough in satellite communications, only in portability.
This doesn't look to be an ISP delivering service either, like people mentioning inmarsat, etc... It's simply a satellite rig that can be used with a multitude of birds. There are a number of ISPs out there that have sattellite capability.
It's a definite issue, but they are a bit misleading as well.
If you consider the satellite communications from a raw radio perspective, you ahve to take this stuff into account... what am I trying to send, how am I going to encode it, etc.
The thing is, as long as the satellite layer has error correction of it's own, TCP will deal with it. (because TCP won't see the errors)
And satellite is no different than any other form of RF communication. It doesn't present any other challenges, other than having a higher latency than other connectins. The distance - signal - noise garbage is the same for any transmitter. You can't just say 'it's far, so it's hard'. It also depends on your transmitter, receiver, output power, etc.
You get the exact same issues trying to engineer a radio linke 20 miles long using microwave gear.