Fiber cut in SF area

Tue Apr 14 22:11:30 UTC 2009

Wireless RF links have their drawbacks:

1. Current GHz Frequency technology places upper limit of 1 Gbps on
point-to-point links, and distance at 1 Gbps is limited. Commercial GiGE
radios are just now appearing, replacing 100 Mbps Ethernet and oc3 SONET
radios. Telco use of wireless links to backup 10/40 GiGE fiber trunks in
metropolitan areas is not scalable.
2. Wireless technology contains hardware plethora of nuts, bolts,
cables, fasteners, custom-tuned crystals, dishes, passive/active
reflectors, in addition to layer 1 tuning best performed by EE
specializing in RF.
3. Relative to fiber optic technologies, there is a very small circle of
RF companies that can install, tune, and maintain wireless links
correctly and reliably.
4. Tower-climbing/working skills are essential.  

But, what is the state of diverse telco fiber paths such that this fiber
cut was not transparent to users in such a key US metropolitan area?    

-----Original Message-----
From: Gino Villarini [mailto:gav at aeronetpr.com] 
Sent: Tuesday, April 14, 2009 1:42 PM
To: Deepak Jain; Jorge Amodio; nanog at nanog.org
Subject: RE: Fiber cut in SF area

Good points, some variables are dependant on the network infrastructure
of the wireless provider.  Localy, the main 2 providers have a
"copper/fiber independent" networks.

Gino A. Villarini
gav at aeronetpr.com
Aeronet Wireless Broadband Corp.
tel  787.273.4143   fax   787.273.4145

-----Original Message-----
From: Deepak Jain [mailto:deepak at ai.net] 
Sent: Tuesday, April 14, 2009 4:36 PM
To: Gino Villarini; Jorge Amodio; nanog at nanog.org
Subject: RE: Fiber cut in SF area

I don't mean to jump in here and state the obvious, but wireless links
are not a panacea. At least a few folks have presented that fiber
grooming has affected their *region*. It's not difficult to imagine that
wherever the "head" link side (or agg point) of these regional wireless
networks is...
probably coincides with a fiber network or other telecom POP. You are
just moving where your last mile vulnerabilities are (slightly.. as you
are picking up multiple power vulnerabilities, Line of Sight, and other
things along the way). 

In the example of a tornado or other weather disturbance, wireless links
are subject to fade just as much as any kind of aerial wired asset. 

Deepak Jain
AiNET

> -----Original Message-----
> From: Gino Villarini [mailto:gav at aeronetpr.com]
> Sent: Tuesday, April 14, 2009 4:12 PM
> To: Jorge Amodio; nanog at nanog.org
> Subject: RE: Fiber cut in SF area
> 
> Here in my area most of business outfits that require maximum 
> availability of Internet or WAN conenctions have implemented dual 
> connections from dual providers, most with a fiber/copper main and a 
> fixed wireless backup.  This trend goes from banks to Mcdonalds
> 
> 
> Gino A. Villarini
> gav at aeronetpr.com
> Aeronet Wireless Broadband Corp.
> tel  787.273.4143   fax   787.273.4145
> 
> -----Original Message-----
> From: Jorge Amodio [mailto:jmamodio at gmail.com]
> Sent: Tuesday, April 14, 2009 11:21 AM
> To: nanog at nanog.org
> Subject: Re: Fiber cut in SF area
> 
> > "Earth is a single point of failure."
> 
> On top of that, one basic principle of telecommunications:
> 
> No matter how much diversity and path redundancy, tons of concrete or 
> titanium sealed fiber vaults you have, in the data exchange between 
> points A and B there will be always two single points of failure: A 
> and B.
> 
> IMHO, this thread is getting way off topic, boring and useless.
> 
> Fiber cut is over, there will be many more, move on ...
> 
> Cheers
> Jorge