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Ariane Launches A New Way To Get Online
pdaoust007 writes "According to the BBC, 'Europe's Ariane 5 rocket has lifted off after three earlier delays, carrying the world's largest commercial telecoms satellite.' There is also coverage from the CBC and some video here." What's really interesting is what's on board that satellite, though: "Telesat Canada, a subsidiary of BCE, has commercialized the Ka-band technology to allow universal high-speed access to internet service. Apparently, this should make high speed access available anywhere in North America. Gear will be $500 and service $60/month ($CDN)."
$60 Canadian is about $46 US Dollars, in case anyone wanted to know. If the latency is good (which it likely won't be), this might not be a bad broadband option.
Send/track messages to 100K people: www.xPressAlert.com
Similar to the current offering from DIRECTWAY and DIRECTV?a tionwide-satellite.html
http://www.high-speed-internet-access-guide.com/n
Cable in Canada runs about $45.00/mo. The modem can be bought for about $60.00 bundled with the service.
"Academicians are more likely to share each other's toothbrush than each other's nomenclature."
Cohen
Two-way satellite internet access has been around for a while now. The biggest problem for satellite internet has been (and will always be) the high latency.
Was asking myself the same question; the only information I could find was on the ariannespace website: "It uses the Boeing 702 satellite bus and carries a mixed payload of 32 Ku-band transponders, 38 Ka-band transponders and 24 C-band transponders."
I imagine it's impressive, considering its size (48 metres solar array!)..
Echostar, DirectWay, and StarBand (http://www.starband.com/ all have two way broadband available in the US. Echostar charges $500 for equipment and $65/mo. They use compression and a modified ip stack to get you ~1Mbit down and ~64Kbit up for HTTP and FTP protocols. Bypassing their ip stack gets you ~56Kbit down and ~128Kbit up.
These systems are widely used by Gas Stations (Chevron), and retailers for inventory/accounting/etc to the central office.
I was forced do go with the Echostar solution until my area got CableModem service. If its the only thing available, then its better than dial-up.
Another problem, Ka band has high losses in rain. May work for Phoenix, may not work for Portland.
Oh well, Canada again pioneering the way of the *non-military* satellites (first commercial geostationary communication satellite was by Telesat Canada as well :)
For cities, like Toronto, this will do absolutely nothing since they already have a few MBps though DSL/Cable.
This is to service people in the Canadian north where DSL and Cable are not possibilities. They have been waiting for High speed for a very long time!
Her name comes from the French spelling of Ariadne - an old goddess of fertility form Crete and Mistress of the Labyrinth. In later Greek mythology, Ariadne's divine origins were submerged and she became known as the daughter of King Minos of Crete, who conquered Athens after his son was murdered there.
SHE does throw dice.
Sorry. Further down the page is the Enterprise version, which gives 8 Mb/s down, 4 Mb/s up.
Microsoft is to software what Budweiser is to beer.
The killer for satellite network access is latency. A typical DSL line has about a 20ms round trip (time for a packet to go from your network to the ISP network and back). If you lived on the equator directly under the satellite (and assuming the satellite adds no latency), you've just added 480ms to the round trip time. Move off the equator and to a different longitude, and latency gets even higher. This kills anything interactive (gaming, VOIP, telnet/SSH) and causes trouble for anything using TCP (window scaling wasn't expected to handle half second round trips).
What is done in some cases is to use special hardware on each end that adjusts TCP to better handle the latency. Also, I've heard some talk about putting caching servers on the satellites (so web access that hits the cache doesn't have to go up and down twice), but I don't know if anyone is doing that.
Radar detectors are NOT illegal in Canada. It is only illegal to operate one in your vehicle while driving. You can still buy them at car audio stores all over Canada. The RCMP and other police agencies have radar detector detectors (which are very expensive so there are only a few of them on the road).
;-)
Yes, someone is probably working on a radar detector detector detector...
Well, daahhh!!!! For the signal to get from Earth-Satellite-ISP-InternetSite-ISP-Satellite-Ear th will be about a second.
To be in geostationary orbit, you need to get to 36,000km above the earth. Since lightspeed is 300,000km/s and you need to travel the Satellite-Earch route 4 times (you to internet and then internet to you), that means the total distance is at least ~144,000km. So that's about 0.5s right there.
The rest of the delay is in preperation and organization of huge packets you want to send to the satellite. Thus the net delay has to be at least 500ms (to ISP) and probably arround 750mb-1000ms. You cannot go faster than 500ms!
The difference here is that Iridium was in Low Earth Orbit (780Km), and would allow short delays, this is in Geostationary orbit (36000Km) so you get delays in the order of 1/2 second, for every packet handshake.
Using standard TCP/IP is a non starter. But while this is a technical problem, Iridium was more of a business problem, too expensive to launch 66 sats for what a few people would pay. If it had got to millions of users, then it might have worked. It was a phone service not a Data service.
The economics for this will be better for all those connection hungry remote users, just dont think it will be like real DSL.
Cheers
John
Well, you're speaking of geostationary satellites which require such a high orbit.
But if you have a system of non-stationary satellites (like the 'Iridium' project), only a few msec will be added by satellite access.
Seems like all of North America is already covered with data service resold through vendors such as Star Band, the satellite is geo-synchronis, so the packet round trip would exceed 700 ms, this amount of latency is a big problem for gaming, VOIP etc., I don't reaaly see how this new satellite brings any new type of service since you can already get internet and data via geo satellites almost everywhere in the northern hemisphere. Mark
Regretfully true, for that thing... Anyone know why they chose Ariane to launch this, as opposed to Titan or Proton? Cheapest option, maybe? - because it can't have been the reliability record.
Real Daleks don't climb stairs - they level the building.
WildBlue promises similar service (1.5Mbps down, 256Kbps up) for 2005, but it looks like Telesat/Viasat might beat them to the punch.
Don't confuse Ka-band (Kurtz-above band) with Ku-band (Kurtz-under band). Ku-band has already been in use for satellite Internet for some time now through (awful) services like StarBand and DIRECWAY, and is also widely used for digital TV broadcasts. Amazingly, even C-band Internet service is available. C-band service requires a much bigger dish, but in some areas this is the best (or only) broadband option. Ka-band service may change that for certain regions of Canada.
I wonder if owners of big dishes will be able to modify them to handle Ka-band Internet. It would probably be inconvenient to share if you want TV as well, but merely adding the decoding module would be trivial if they released a kit. It's already relatively simple to add support for new kinds of services, such as 4DTV.
Unlike this project, iridium wasn't a satellite. It was a constellation of satellites - 66 satellites + 14 spares!. Just think of the difference in costs. Service isn't $60USD, it's $60CAN. You could hardly say "hello" to your Mother for that much at Iridium's initial asking price. As for rural folk not "really needing" Internet, well none of us does, but we pay through the nose anyways. I live in a city of 500,000 people where DSL is not available in my neighborhood, and cable costs almost the same as this satellite service.
The physical minimum latency for a geosync sattelite (at an altitude of 22,300 miles) is 120ms, if anyone is interested. Of couse, you'd double that for an actual ping, since the signal has to go both up and back.
To ping the satellite, yes. However, that is of limited interest - since most people want to actually communicate with other internet hosts - not just their edge router. Plus, as far as I know the actual SV is just operating in bent-pipe mode -- there is no packet-level processing on board, so there is no actual router inside the satellite to ping. (Disclaimer: My IP-over-satellite experience is based soley on setting up VSAT systems -- these consumer products might be engineered differently.)
There are two round trips for a packet going via satellite. From your computer to the satellite, back to an earth station (240 mS) , across the internet, then the reply packet goes from the earth station to the satellite and back down to your house (240 mS again).How does the Slashdot Effect happen given that no slashdotters ever RTFA?
Except that the request packet travels 44,600 miles, and then the return data travels another 44,600 miles.
Ie:
home->sat->isp->sat->home == 480ms.
Um, ever used satellite internet? How's 128K down and 64k up sound to you? After you purchase your $1000 bi-directional dish and have it installed, and pay $100/mo for service, it would be cheaper to have an ISDN or Frame relay ran to your home or business. I'll pass.
:)
Couple points:
Advertised rates are 750k down, 128k up. Yes, slightly over $100/mo is what that costs. Are any frame-relay or ISDN services much less than that?
The worst part is there's no way around the time it takes the signal to travel the 88,000 miles to and from the satellite TWICE to get a packet to the internet and back. Right around 500ms latency, minimum.
So, if it's "cheaper to have ISDN or Frame relay" then by all means... but it is NOT cheaper in many, many areas of the US. In some more rural areas, you just can't get any high-speed services at all. The rural telco will just laugh at you, or offer you $1000/month prices. (To their defense, if you're many many miles from the nearest CO, building a T1 out to you costs BIG BUCKS for them)
It all depends where you live.
Cool thing: Starband is offering a self-pointing dish system for mobile homes etc. Try getting frame-relay to a moving target!
What I'm looking forward to is more constellation-based low-orbit satellite systems with higher bandwidth. Latency is much less of a problem, with orbits of 300 miles instead of 22000. But the economics of such a system just doesn't quite work yet. (Think of the problems Iridium has had)
- Peter
INsigNIFICANT
Bandwidth is already limited on existing (Directway) satellite internet systems by d/l limitations. Pull down your whole quota and the system slows you down to 56k . . . last I heard from a friend that had Directway, the quota works is like a bucket with a hole in the bottom. The hole in the bottom drains at 128kbps and the fillstream at the top runs a 56k. You can d/l at full 128kbps until the bucket empties . . . then you drain the bucket as fast as it fills (56k) until you stop using the system and allow the bucket to refill.
The ANIK-F2 has antennas that will cover both North and South America. So you can probably expect them to offer high-speed internet services to any market that will pay for them :]
For web browsing the trick is simply to set your browser to retrieve a lot of items in parallel rather than a smaller number serially. By default browsers are set to pull back only a few items at a time (IE and Firefox are both 4) but for a satellite connection this needs upping to 30 or so.
Because the satellite combines packets into larger frames then net effect is that web pages then come back in a similar time across satellite to DSL. The difference is that with a satellite the page will then tend to appear all at once with all items after a half to one second, whereas with DSL the page fills up over the same time frame with individual items as the browser goes through the fetch/display/fetch next loop.
You don't seem to understand the idea of TCP ACK windowing - you DON'T ack each packet.
.ISO image, for example) the latency is a non-issue.
Instead, the sender starts sending packets, and will send some number N packets before requiring an ACK. The receiver will NOT ack each and every packet, but rather it acks groups of packets.
For example, the sender might start with a window of 100 packets - it will send 100 packets before pausing for an ack. The receiver might ack the first packet, then ack packet 10 (implicitly acking packets 2-9), then packet 50, then packet 100. Upon receiving the ack for packet 10, the sender might increase its window size to 1000 packets.
Thus, unless the delay*bandwidth product is HUGE, the data will keep streaming until either a) there is a NACK due to corruption of a packet or b) the job is done.
So for non-interactive moving of freight like BIG FTP transfers (downloading an
However, interactive operations like browsing suck because you pay the startup penalty for each HTTP request. However, modern browsers have HTTP pipelining, wherein the broswer can open the connection, request the main document, then, as the document comes in and is parsed, send additional requests (for images, etc.) without closing the connection and before the main document has been fully retrieved, thus burying the cost of the startup in the transfer.
However, this is less effective with everybody and their dog's website putting images on a seperate server, thus requiring a second channel to be opened.
www.eFax.com are spammers
According to what I've been told the Ka-band is capable of trasmitting and recieving as much data as a standard OC-192, which makes it the largest satellite throughput I've ever heard of..of course, its up to the 'customer' on how much bandwidth and time they buy on the satellite.... So, it's gonna be interesting to see what happens with this one
Ariane launchers are not reusable. So the name sticks to a design rather than a specific launcher. More info on the ariane family.
Definitely mass. Ariane 5 is the only working and available rocket that lifts 6 metric tons into orbit.