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Ask Slashdot: Good Satellite Internet For Remote Locations?
EdIII writes "I've been looking for a decent contention service (4:1,10:1) in South America and I am not finding much. I have also heard that some frequency bands are a lot better at cutting through cloud cover. This is for a fairly remote ground station with reliable power generation, but also routinely cloudy. I would need at least 3/1Mbps with hopefully decent latency. What's your advice Slashdotters? Yes, I know that some of the solutions can cost 20K for deployment and 2-10K per month for service. Feel free to to tell me about a good commercial service. There is another ground station that might be deployed in north east Alaska."
Simple answer is you won't. There are no "good" satellite internet for anything. With luck you might find "adequate" or "usable" satellite internet. But don't let any one lie to you and tell you that they have "good" satellite internet. There is no such thing.
Supporting World Peace Through Nuclear Pacification
Well, if you want decent latency from a satellite network, I think the LEO Iridium constellation might be your only option: 10-20ms rtt vs. 500-600ms rtt for any geosynchronous satellite.
http://www.scribd.com/doc/49385912/Iridium-9602-Data-and-Inmarsat-C-latency
Though actually, it looks like the practical rtt to another the internet can take 1800ms over Iridium, since it has to bounce the signal around other nodes until it can get to one of its ground stations :/
Of course, Iridium data rates are in dial-up territory. It seems like you might be able to get low-cost consumer grade satellite services from DirecTV or something, using Iridium as the dial-up uplink component. But it also sounds like you'll be transmitting more data than you'll be receiving, if this is for data collection :/
Given that it also sounds likely you're looking at remote sites near the poles, Iridium may be your only option, since it gets pretty difficult to hit geosynchronous satellites beyond 70 deg latitude. So you might want to be optimizing your data transfer needs to fit through a tiny pipe, augmented via occasional sneakernet.
In short: :/
Translation: "Dear Slashdot, the last RF engineer we kidnapped and enslaved has unfortunately died, can you please suggest a commercial and less bleedy replacement for our darknet?"
I want to delete my account but Slashdot doesn't allow it.
That sure will work in the middle of the wilderness. Just cary a giant spool of fiberoptic cable wherever you go, and unwind. It has the benefit on top of satellite internet that you will never get lost. Just retrace the internet back to Verizon's office.
Come on, did you even pretend to read the title?
AC will be the next /. editor.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
I know you say that you know of solutions which cost 2-10K, but what is your actual budget? A fixed VSAT install seems to be what you are after, it will give you 600-700ms return latency but it will give your decent speed (go for a DVB-S2 service for good value for money). However, you will be looking in that price range you mentioned... I only working with roaming VSAT services (where you have access to beams on various satellites all over the world). We pay $18K per month for a committed rate of 2048/256 which is burstable up to 10240/256. A fixed service on one beam will be significantly cheaper then that though...
First you need to mention where you are exactly. Internet service over satellite is usually sold through local providers. Furthermore, different satellites have different coverage areas.
Second, if you want high speed broadband, you will need a Ku/Ka band (small antennas) satellite terminal. The problem is that in South America, it is more common to use C band (big antennas) satellite terminals that are slower than Ku band since the spectral bandwidth is smaller and more expensive.
Third, the latency is basically the same for all Geostationary satellites and in practical terms is about 250ms from the transmission latency and 150ms for the latency of the entire transmission chain. As systems improve, this latency gets reduced but the transmission latency only depends on the relative position of the terminal to the satellite and the speed of light.
Forth, above 70C latitude it is not possible to provide Internet over satellite with geostationary orbit since there isn't enough visibility of the satellite on the horizon.
Fear is the mind-killer.
I'm not sure what moron told you 10 second latency but as a former NA Hughes customer I can tell you it was an order of magnitude less. Best/worst case was 700/1500ms respectively using their consumer equipment. Unless you're doing FPS games, or VOIP you'd hardly notice the latency. Business wise, Hughes also does a pretty good job of taking care of their customers. The support escalation ladder is short and getting to engineer level staff painless. Having had to deal with Crapcast support and their half measure remedies, I've found myself wondering if I might not be better off switching back and taking the performance hit.
Two of my imaginary friends reproduced once
Get Iridium for latency-sensitive traffic (if you have any) and a geosync provider for bandwidth, and then configure QoS on your router to meet your needs.
The cost of a decent router will be incremental compared to the dishes, and you gain a degree of redundancy. (Latency will go out of spec or bandwidth will be at capacity, depending on which link failed, but it is better than nothing. At least you can send an email explaining the situation.)
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According to the latest ruleset, this post should be modded as Vorpal Flamebait +5.
As a satellite technician, I think I can help answer some of your questions.
1. "I have also heard that some frequency bands are a lot better at cutting through cloud cover".
This is true. C-band has about 10dB less rainfade than Ku-band does, and Ku outperforms Ka-band as well (Not sure of the exact number as I don't do a lot of Ka links). C-band also requires larger dishes. You have to take into account what the acceptable availability is as well. 99% availability is quite possible and just requires a proper link budget (basically a series of calculations of gains and losses in the signal path which takes into account dish diameters/efficiencies, weather and satellite properties, among other things). Getting high reliability when taking into account weather is usually a lot easier on C-band, but if they are using an old bird with low output power or poor sensitivity, then a good Ku setup will outperform it.
2. "I would need at least 3/1Mbps with hopefully decent latency"
Latency is usually pretty fixed. The physics say it takes about 250ms for the signal to travel from your earth station to the satellite and back to the other earth station with an RTT of about 500ms. Any additional latencies are created by the FEC coders and access methods. The worst will probably be something that uses older Reed-Solomon over Viterbi (not used much anymore. Everyone has either already moved away from this 50 year old tech or is doing so right now) on a TDMA access system. I would expect an 850ms round trip time on this type of old system. The best will be a system that implements Turbo Product Coder or LDPC on an SCPC link (Dedicated link). I would expect about 600-650ms round trip. If you get on a shared network, anything modern will be using at least TPC and possibly LDPC if they're using DVB-S2 and you'll probably see an RTT of about 750ms (best guess on my part. each network is different). Additionally, using a shared access system will introduce jitter of which 50-100ms wouldn't be surprising to me. SCPC links tend to be quite good for lack of jitter. Getting the types of bandwidth you want is really a matter of contract.
3. "I've been looking for a decent contention service (4:1,10:1)"
On any shared access system, contention would be a matter of contract, and the lower the contention, the high the cost. When you start getting into 4:1 or better you're probably better off looking at a dedicated link, even if its not as fast as what the shared service is advertising. Personally, I'd actually rather pay for slower access with more generous transfer allowances than a fast connection with a really low transfer allowance. If you do go with a shared service, read their FAP carefully and calculate how much you can actually transfer taking into account transfer speed, FAP and transfer limits and compare this with your needs. It may also be to your benefit to either have multiple accounts with the same vendor or multiple vendors where you can switch between them as the month goes through. It could be cheaper than a more expensive link or cheaper than a dedicated link. Your budget will determine this.
4. Regarding "Globalstar, Iridium, Inmarsat, Thuraya and other similar systems"
These sorts of services will not provide the types of speeds you want and will cost you a small fortune in transfer fees, though they will have much lower latencies.
Unfortunately, satellite space is very expensive, as strider- indicated (and without sounding like we're colluding, I do know that he knows the industry). You really get into the "fast cheap reliable - pick two" and it should be more like "fast cheap reliable - pick one and hope for another one.... the third is right out" when you are dealing with some of the shared access satellite providers.
some karma... and kinda lukewarm about it.