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Re: [LUG] forum?

 

On Fri, 30 Jan 2009, Simon Waters wrote:

Tom Potts wrote:

Dependence on telcos will result in all sorts of ill thought out stupidity -
there are moves afoot to sideline P2P 'in case someone uses it for
downloading music that only costs 10* the price the musician gets for it to
keep the parasitic music industry going and no other reason'  OK so we can
run everything over port80 using tunnelling but  belts,braces and pringles
aerials .... I can see 54Meg point 2 point connections costing  <£100 for
10km reach...

Speaking as someone who helped build 10Km wifi links, we did it for
cheap, but it wasn't easy. And cheap is a relative term - antennas and
decent cables/connectors cost money - fortunately our radio guy had all
that already.

54Mbps may be the spec on the devices, but over long distances WiFi
can't do that (nor can WiMax do its 70Mbps over distance). Some Intel
wifi devices use to let you tweak the algorithms for transmission, and
we got significantly better than 56Kbps out of the links, enough to call
it broadband and connect a few cottages.

I think you are stuck with licensed radio links for most performance
networking - like - urm - the telecoms companies do.

I was once heavilly involved with rural broadband projects in the South west - Buckfastleigh in Devon and Penwith+somewhere else in Cornwall. Google might tell you something about the Buckfastleigh Broadband project however, I doubt you'll find much about 1st Broadband who ran the commercial side of it.

Basically it failled. It cost too much and the punters weren't willing to pay and BT were chasing us and enabling the exchanges way before their target dates... 1st Broadband went bust twice and I eventually took it over myself with the help of an RDA grant to keep the Buckfastleigh side going (had 50 'customers' here) before BT enabled the exchange.

It cost a lot because we did it properly - we used decent (for the time) outdoor kit, all at rooftop level, to guarantee line of sight - paid farmers, etc. to host base stations - relied on the goodwill of others to host other repeater nodes. It was costing us upward of £250 for each install by the time we took into account the cost of the hardware, the cost of the person to go up the ladder and fit it (we used local sky installers as they had insurance and tools), consumables, etc.

We made it work, but it was expensive, and it took just one P2P user to kill an entire segment of the network.

VoIP over Wi-Fi isn't reliable either - sure, you can make it work at home, but all it takes is one PC to get/put a big file and it'll kill a conversation. There are more expensive access points now with traffic management though - but it's still not perfect. VoIP is inherently full duplex and Wi-Fi is half duplex. VoIP sends 50 packets of 160 bytes per second each way. Some of the cheaper access points take the same time to do a link turn-around as a single packet.

Our longest link was 17.5Km from Marldon masts to a farm on Dartmoor. That was using a pair of 2' dishes and 5.8GHz kit. The longest Wi-Fi link was about 10Km - pure line of sight with a high gain onmi at the base station and an 18db grid antennae at the client end.

Buckfastleigh was described at the time like living in an egg box... Trying to get line of sight was hard at times - then the town council whinged that were were interfering with their CCTV system....

When I see churches in rural areas, I see a big communications tower (you
can hide a wifi antenna very easily)

Urm since wifi is predominantly line of site - you can't really hide
them. Although I know this guy who can make very stylish antennas for
you, and know which guttering has the best microwave properties if you
prefer the weatherproofed look.

One church let us stick a satellite dish antenna on their tower for
demonstration purposes, but I'm guessing that we wouldn't have got
planning permission for a permanent fixture.

We approacked some churches. They all said no. Buckfast Abbey did help us, but only because we gave them a nice feed for free.

What I never realised was that many prominent hill tops have regular UK
power sockets on top of them, to plug in all the radio gear. The radio
hams have been here (there) before. So often it is just a case of asking
whoever is paying the electricity bill.

Good luck to anyone who tries this - again. I really don't think it's worthwhile persuing anymore - yes, I know there are still some communities outside the rach of BT, and for them it may work - as long as there is a genuine commitment from the subscribers, but general-purpose? Forget it.

Or maybe I'm just too cynical over it all - I did dedicate a lot of my time and efforts to this and after my experiences, I won't ever do it again!

Gordon
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