[TriLUG] wireless bridge?

[Tanner Lovelace]

On Wed, 2003-03-26 at 20:06, Jim Ray wrote:
> I'm trying to get some NFR equipment from SMC for that purpose.  They
> seem to stay out of stock.  Me thinks some tuned Yagis or parabolic
> antennas with some Layer 2 hardware would make a sweet point to point
> connection with DS3 speeds and no major price tag.  Life is good.

Note however, that depending on how it's setup, it can actually
end up being against FCC rules (for these unlicensed transmitters
that would be FCC Rules Part 15).  Depending on how much gain your
antennas have, you'll need to make sure that the Transmitter Power 
Output (TPO) is lowered 1dB for every 3dB of gain over 6dB that your
antenna gives you (note this is just point-to-point, rules for 
point-to-multi-point are more stringent).  To put this in other 
words, if your antenna has 24dB gain (not an unreasonable figure),
that's 18dB over 6dB.  If you have a 1 watt transmitter, you would have
to lower the power output by 18/3 or 6dB (1/4 watt) to stay within the
rules.  

If you don't do this, you may or may not run into problems.  The 
FCC doesn't have that much personal to do enforcement but the do
act on complaints.  Since the 2.4GHz band's primary user is Ham
Radio, it's very likely that someone there might complain if your
transmission is interfering with them.

Many people think that you can do anything you want in the unlicensed
2.4GHz band that 802.11b operates in, but unfortunately that's not the
case.  

Note that one way you could run more power is by becoming a licensed
ham radio operator.  The Part 15 power restrictions would then no
longer apply to you, but instead Part 97 (ham radio) would.  The 
downside to this is that a) you can't run anything commercial and
b) you can't use encryption (although you can use authentication) 
while under Part 97 rules.

Cheers,
Tanner Lovelace
-- 
Tanner Lovelace |  lovelace(at)trilug.org  | http://www.trilug.org/
--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--
GPG Fingerprint = A66C 8660 924F 5F8C 71DA  BDD0 CE09 4F8E DE76 39D4
GPG Key can be found at http://wtl.wayfarer.org/lovelace.gpg.asc
--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--
 101010 - The Ultimate answer to Life, the Universe and Everything.