Re: wireless lan in the absence of a good isp
I have been on a system very much like that for about a year. It works very well for both internet use & for VPN access throughout the community.
Our wireless network is secured by MAC filtering; whilst this is not the most secure, it is the easiest method to stop other people using it.
As far as antennas go you don't need particularly expensive ones, but they do have to be direct line of sight, so need to be roof mounted: you'll need a very high roof for the main access point (ours is on the local church).
Best of luck
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