Update: CSX train derailment

Dave Stewart dbs at ntrnet.net
Sat Jul 21 17:07:47 UTC 2001


At 12:50 PM 7/21/2001, up at 3.am wrote:
>Yes, I can see that; but I imagine you could handle this much the way
>fiber is handled near the shoreline.  Bury it a few feet under the mud or
>sand.

Keep in mind, too, that every crossing isn't going to be a nice, deep 
river... I can think of hundreds of cases (and so can you) where the 
crossing is over a shallow creek or fairly deep ravine (no water at all!) - 
yet difficult at best to trench it in... so cables, pipelines, etc, ride 
the bridge...

Then your friendly local tropical storm comes along, drops plenty of water, 
and the bridge washes out.  Now what?  Reroute everything, of course.  Or a 
tank truck catches fire and destroys the bridge (as happened in Atlanta not 
long ago - sure, it was I-285, and I don't think any cables rode that bridge),

Obviously when routing cables, you have to deal with the cost/benefit 
ratio.  What are the chances of any single point suffering catastrophic 
failure?  How much will it cost to trench it in instead of riding a 
bridge/tunnel?  You make a decision, then you deal with the consequences if 
you're wrong.

More than worry about exactly what method is used for routing cables, I 
agree with building redundancy.  Because no matter how you armor/protect 
your cables, something CAN occur that'll break through that protection... 
but if you have a backup in place, routed another way, with automatic 
failover, you barely notice.  More importantly, your customers DON'T notice.






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