If you were in a government Cyber-warning center

herb at tomobiki.urusei.net herb at tomobiki.urusei.net
Sat Apr 27 03:39:14 UTC 2002


Chris Kilbourn wrote:
> 
> 
> In the past few years on NANOG, I've noticed a strong correlation between
> train derailments and network outages. (Not to discount the backhoe
> correlation in any way of course...)
> 
> The question I have is this:
> 
> If fiber runs are trenched into the railbed, and we know that trains
It is not normaly *in* the railbed.  The Right of Way specifies something 
along the lines of 20 feet in either direction 90' from the mapped path.
The fiber is normaly far enough away that a crew can safely work on the 
fiber and the train can safely (slowly) pass at the same time.

> go off of the tracks every now and then, what, if anything, is being
> done to harden the conduit?
Fiber is not always trenched.  Sometimes fiber is strung on poles next
the the tracks. 

> Would trenching it deeper help? Has encasing the conduit in a
> steel-reinforced channel been examined? Or is there something about
The harder you make it for them gremlins to get in, the harder you make 
it for you to get in when you need to.

> laying conduit next to track and the accident modalities that I am
> just missing here?
Sprint stands for Southern Pacific Railroad (INternal Telcom--not sure of 
that last part...).  Guess where Sprint's fiber is?

> Given this week's higher frequency of rail accidents and their
> attendant network disruptions, it seems like the cost/benefit of
> looking at this issue might have shifted a bit.
Trenching where there is not already an existing right of way (This is 
worse in a urban area) is very expensive.  Expensive to the point 
where you have to have multiple companies go in on the trench to make
it even resemble something cost effective.  Take a look at the 
trenching done a few years ago on the San Francisco Penensula for 
example--Every few hundred feet there are 6 or so manhole covers 
marked XO, PB, WC, MFN, ATT, etc.  Absent from the lineup was Sprint, 
which has the CalTrain run from SF to Gilroy. 

I am surprised that BART does not try to make some quickie bucks by
stringing fiber on it's right of way.  We can call it Bay Area Rapid 
(transit) Fiber--BARF.  =)

> I can only see these right-of-ways becoming increasingly valuable
> over time and in our post 9/11 environment, this seems to be an
> area that seems especially vulnerable.
The old right-of-ways are for trains.  The fact that you can lay
fiber is just iceing.

/herb



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