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Philip Dore wrote:
ADSL via Satelite is now available countrywide, it's a bit more expensive than via the phone line - take a look at http://www.btopenworld.com/satellite/.
It is just BT reselling an existing VSAT satellite product, it isn't anything new. I dare say BT probably get a good bulk discount. It is broadband nor ADSL of course. The problem with satellites is latency. The satellites are geostationary, so the signal must travel about 45,000 miles before they are put into the usual optical fibre network. Even at the speed of light this means you will get half a second of latency per round trip just going to the satellite and back twice, even a simple web pages retrieval can easily require 3 or 4 round trips (Many require more, but web browsers are multithreaded, so they will probably happen concurrently after the first few) - do the maths - that is 2 seconds per web pages on top of any other delays. Fine for watching movies, or listening to Internet radio stations, or even downloading Linux distros, but conferencing is going to be unpleasant, and even normal surfing may be painfully slow. For normal broadband requirements in rural areas you want wireless ground to ground systems, or at worst bouncing signals of the Ionosphere, or polar orbiting satellites. Better still for many sites would be if BT enabled ADSL for those exchanges that have enough people that assuming a decent take up rate 20% of households, would be economically viable. If it is so fast why don't BT quote comparitive time to download a well known web page - I'd even settle for www.microsoft.com ? More bizarre is BT don't quote a contention ratio figure for the service. Simon -- "Don't get me started on intuitive. You know what's intuitive? Fear of heights. Everything else we call intuitive, such as walking or using a pencil took years of practice." - Don Norman -- The Mailing List for the Devon & Cornwall LUG Mail majordomo@xxxxxxxxxxxx with "unsubscribe list" in the message body to unsubscribe.