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Re: Plano, TX Legacy: Fiber Provider or Wireless & Wireless question
From: Scott McGrath <mcgrath () fas harvard edu>
Date: Wed, 20 Aug 2003 17:30:03 -0400 (EDT)

Wireless is a good option but you might want to look at the licensed 
services as well.  Licensing in  most cases is a formality handled by the 
vendor along with a nominal "user fee" sent to the FCC.

Unlicensed systems are regulated by part 15 of the FCC regulations which
read DEVICE MUST ACCEPT INTERFERENCE this means if another service with
primary allocation in those frequency bands begins to interfere with your
service you are up a well known creek without propulsion.

Secondly if your device/link interferes with a licensed device YOU must
fix the interference at your expense or terminate the operation of the
interfering device.   

This part of the US code has the full power and majesty of the federal
government behind it and since the primary services in these bands are the
"Government Radiolocation Service" in fedspeak better known as Military 
Radar to the rest of us the  enforcment stick is quite large
(5-10k$/Day fines and prison terms)

                            Scott C. McGrath

On Wed, 20 Aug 2003, N. Richard Solis wrote:

Wireless is a good option with a few caveats:

1. At the speeds you are talking about, you need line of sight. 
Usually, this means getting up high to account for curvature of the 
earth and clearing of what is called the fresnel zone for the particular 
frequency you are using.

2. You will need to use some of the higher frequency systems to get link 
speeds of a gig or more.  There are 23ghz unlicensed systems as well as 
60ghz unlicensed systems.  The 60ghz systems will get you higher speeds 
but the link distance will be on the order of hundereds of meters.

3. Link planning will be a critical exercise.  If you really NEED the 
high availability, you can get it by properly considering the distance 
you need to go, the speeds you will use, the frequencies you will 
transmit at, and the statistical expectations of weather and other 
factors that will affect the total path attenuation the system will 
encounter.  Systems that average availability of 99.99% are commonplace 
and 99.999% can be achieved by using shorter path distances.

Try the guys at www.ydi.com.  They will steer you right.


Brennan_Murphy () NAI com wrote:

 > Looking for any advice or pointers for obtaining
 > multiple Gig links (last mile) in the Plano, TX
 > area.  The abundance of fiber options here seems
 > to be decidedly underwhelming. Looking for suggestions
 > including creative options such as wireless. I
 > need to get from Plano to any closest better place for
 > picking up multiple Gig Internet links.  Wondering
 > too what other large companies in this area have done
 > for large internet links...any advice appreciated.
 > Also, I'm reading now that more ISP's are using
 > wireless for last mile provisioning on the new
 > unlicensed frequencies.  Was wondering if anyone
 > had experience using Dragonwave or any similar
 > wireless products in Texas. Do sandstorms and
 > golf ball sized hail pose significant issues?
 > Severe thunderstorms?  Would like to chat with
 > anyone with significant wireless experience in
 > the Dallas area. WOuldnt mind speaking with an
 > unfluffed sales person eitehr. :-)

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