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Two-Way Satellite Internet Is Here!
spectro writes: "Wired is reporting the first two-way satellite Internet service has been launched by StarBand.
The service promises speeds up to 500Kbps down and 150Kbps up, but a ping latency of about 400ms, so gamers are out of the question. Anyway a nice alternative for those of us who cannot get DSL yet, but watch out... The Evil Empire is part of the joint venture." It's nice to know that someone has finally made the leap, after years of promises and millions of R&D dollars. Check out the article for information on some of the competition, too.
The numbers are very easy to calculate. 22,000 miles, times 4, divided by 186,000 miles per second; that is 473 mS just for time of flight.
The service should shine for big downloads, but be rather poor for highly "chatty" stuff, with many request-response pairs. Loading web pages with many small objects would be rather disappointing, I should think. Checking POP3 email, if there are many small messages, would be pretty poor.
It's just that it's not that commonly used. I installed a bidirectional, mobile satellite internet link 2 years ago, with T-1 speeds. Granted, not the cheapest thing to do, but it was still there. And it sucked, at least for web surfing, which was why we installed it. Unfortunately, we didn't have much of a choice since we needed a mobile solution, and Ricochet wasn't up to speed yet.
Typically, satellite data streams have about a half second latency. That means you send out a ping to your next hop, and it's at least 500ms before you get the response. Now when you're doing a stream of data in, this isn't so bad. You have a half second latency when you're setting up the connection, but then you have a nice even data delivery. However, for things like web surfing where you're setting up lots of connections (up to 30 or 40 per page sometimes), it's unbearable.
Satellite internet connections are useful if you're in a remote area and can't get anything else. But if you have anything else, even IDSL, you're going to find it a better choice for things like web surfing and gaming.
-Todd
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"The details of my life are quite inconsequential..."
Why not just use AOL?! 2k up and down is all anyone really needs. 2000 bytes is alot.
This is very empowing stuff.
And that's not the half of it. Imagine you're a foreign newscaster stationed in the backroads of Afghanastan or Somalia. Do you know how much your life is put in danger every time you try to "link up" and communicate with the agencies back at home? Most often, the telephone infrastructure is nonexistant, and the rest of the time, it's bugged.
Or imagine you're the driver of a van delivering groceries and blankets to the homeless. Do you know how many lives are lost every year owing to exposure, simply because of miscommunication between relief agencies and dispatchers? A continuous link with home would solve that dilemma while providing incidental benefits like letting the homeless check their email or search for jobs on the internet.
Radio will get you somewhere, but cbs are subject to a lot of abuse. Recently in NY, disgruntled ambulance drivers were (illegally) jamming the airwaves by blowing on the receiver each time a dispatch went out to a non-union ambulance. Thankfully, no one was (apparently) killed by the practice, but just the same, it's a scary prospect, and it'd be a lot harder to jam a satellite feed.
The sooner we realize real lives are at stake, the sooner we'll embrace this technology, for the greater good of humanity.
-- Anne Marie
Sure, wireless brings forth a whole new series of security concerns. And that means encryption has its part. But it does nothing to address insecure hosts on persistant broadband connections.
What do you want to bet that the new satalite service providers will do the same as their xDSL and cable competitors and ignore this problem. But hey... they have encryption.
The higher the frequency allocated for the service, the tighter the spot beams with a given dish diameter, which means you can end up with the geographic equivalent of a dynamically distributed cellular communication system deployed via a single satellite with the main drawback being that you are sharing a single point of failure as well as a bandwidth bottleneck. However, at these high frequencies satellites can be parked much closer to each other in the same orbital so the bottleneck and failure vulnerability can be minimized by requiring a bit more complicated ground station to allow a fixed dish to rapidly switch between co-located satellites.
The rain problem is serious, but can be minimized, at least on the downward leg, by increasing the energy storage capacity of the satellite to power through the weather. IIRC the upward leg has a bit more of a problem with heavy weather because, although power is quite available on the ground, the scattering occurs far from the satellite (clouds are only a few miles in altitude whereas the satellites are about 20 thousand miles away). On the upward leg it is a bit more problematic due to the fact that arc very tightly which further increases the density of communication via demultiplexed (parallel) communication channels.
The delay time introduced by going up and back is less than typical human reaction time (about a quarter second) so its just fine for most practical uses -- even interactive ones other than games where people are pushing human reaction times to the sub 100ms ranges.
Starband is probably in these high frequency ranges since they do have a bit of difficulty with heavy weather, although I haven't been able to locate their FCC filing online to see exactly how high the frequency actually is.
Seastead this.
While the article doesn't come out and say it, I'm guessing there will be serious total bandwidth limitations- since there are no tracking antennas, and since this is referred to as part of a satellite TV service, it must be from (and probably to) a satellite in geosync orbit. All traffic is probably going to just one satellite. Once a lot of people sign up for this- popularity will kill it- since I'm sure that they can sign people up to long term contracts faster than they can put more transponders up.
Plus there is the fact that anything beamed to you is probably also being beamed to everyone in a multiple state area around you. I sure hope they have some *strong* encryption built in. They ought to be doing something better than DES, no?
I hate to say it, but the microsoft backed Teledesic system is a much better system (many satellites in low earth orbit- kinda like a cellular system) the satellites are closer and cover smaller areas, so the amount of bandwidth/satellite is much smaller.
Hardly anyone wants to sell you a simple net connection anymore. What's with all the useless addons? ISPs are always trying to be their own portal when they can't top Yahoo. Best Buy tries to get you on MSN when you buy a refrigerator.
Now to get satellite net access you have to buy a whole new PC, and it's still $60 a month?
Dammit, give me some hardware and tell me what I should set the IP and DNS to, and charge me less!
but a ping latency of about 400ms so gamers are out of the question.
:).
.118 (approx) seconds now multiply by 2, we have to go both ways. we have .236 seconds (approx).
I rember when i thought light (186,000 miles/second) was fast haha. Now 400ms a second isn't round trip time for light from nowheresville -> Satellite -> Backbone router but the handicap makes up for a damn sizeable chunk
Let's investigate.
For example, if the mission requires a geostationary orbit, which can be achieved only at a distance of about 35,000 km (22,000 mi) above Earth.
I got this from MSN Encarta. MSN... like their operating systems, probably can't be trusted
Lets do some calculations(my favorite). For light to get to the satellite it takes
Now a handicap of 236ms before you get on the net leaves a little to be desired. Like, Damn I wish light were faster.
Time is Change