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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)."
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!
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...
Good points; however, with a proxy TCP stack providing increased TCP buffer sizes at the gateway, and gateway-side ACKs, along with other methods, TCP over satellite is not only possible, but practical.
I've used satellite connections, and they are just fine. You get used to the latency, especially if you have a lot of bandwidth (say, 8 Mb/s). VoIP over satellite is awkward at first, but I understand you get used to it after a while.
As far as rain fade, modern satellite systems adapt power output for attenuation due to weather. What works in Phoenix *will* work in Portland.
Microsoft is to software what Budweiser is to beer.
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.
uhmmm.... no. Have you heard of TCP's 'sliding window'? TCP doesn't just send one packet and wait for its response before sending another, etc.... after your connection is established, if packets are not dropped, more and more packets are sent at once before their ACKs are received. There can be up to n packets 'in the network' at once, where n is the dynamically determined window size.
Will you still have huge latency? Of course. But UDP will fare little better than TCP, and your bandwidth may still be appropriate for those ISOs.