[sclug] Long distance Wifi

[ed]

On Tue, 28 Feb 2006 10:15:17 +0000
Bob Dunlop <bob.dunlop at xyzzy.org.uk> wrote:

> On Mon, Feb 27 at 07:21, ed wrote:
> > > We have a place on a hill in the depths of Wales and would like to
> > > get broadband.  Unfortunately we are too far from the exchange to
> > > get it  directly although some friends have it in the village down
> > > in the  'valley'.  I was wondering about the possibility of using
> > > point-to-point  antenna to do wifi from our friends.  I've seen
> > > loads of commercial and  'pringles can' antenna on the web but
> > > nobody seems willing to put a  distance on their performance.
> > 
> > By pringles can, are you referring to 'yagi-uda'? These have better
> > performance on ptp networks, you will need one at each end of
> > course.
> 
> I have a home made Pringles antenna and by comparison with a commecial
> 14dBi yagi I reckon it ways in at about 12dBi.  The Pringles can is a
> lot more compact and useful when traveling but I'd hate to have to try
> and waterproof it.
> 
> As for range both were very useful for snooping on the villages WiFi
> ISPs traffic at a range of 1-2km.  I live on top a hill and have a
> good line of site to the village.
> 
> Hi Ed!  do you remember this thorn in your side :)

You're no thorn! I'm just sorry the project was a complete failure for
your village.

Hows the kernel hacking going?

> > > First, is this actually possible?  How far can these antenna work?
> > > 
> > > Our  closest friends are about 1km away in direct line of sight.
> > > Second, is it legal?  How do people like BT view sharing a
> > > broadband  line like this?
> 
> The ISP that Ed worked for provided me with a nice box on a pole with
> the antenna and Ethernet bridge built in to cut down on any lengths of
> coax which are very lossy at 2.4GHz.  The antenna was only 9dBi but it
> easily maintained a 5.5Mbps link to the church tower 1.2km away.  Such
> a pity so much of the ISPs other infrastructure didn't work as well.

Incidentally, q-networks who provided that authentication system doesn't
seem to exist these days.

There were some problems too if I remember with the AP interface that
your bridge was associated to, some times it was associating either with
the police house, or with a different sector, I don't remember which.
 
> I had two Smartbridge airBridge TOTALs that I gave to a community WiFi
> project in Southampton which they were going to try and build a point
> to point link with.  Unfortunatly the project died before they
> actually got to try it.
> 
> Ed do you know if the TOTALs can actually be used like this ?

No, they only talk to an access point IIRC. There were some smartbridge
access points though, I know we didn't use them in your village though.

These might be what you're looking for, smartbridges are good for
outdoor units http://www.smartbridges.com/products/appt.asp.

-- 
Regards, Ed                      :: http://www.usenix.org.uk
:%s/\t/  /g                      :: proud unix system person
:%s/Open Source/Free Software/g