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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: fiber cut 19 May/PM -> 20 May/AM in Ashburn, VA (lawnmower?!)
Dan Armstrong <[email protected]> writes: > Forgive me, but > > Isn't Sonet usually deployed in a ring? Why the heck would a fiber > this important not be? sonet, obviously, does not *have* to be in a ring, but it often is. unfortunately, a fair percentage of the time, the additional protection offered by a ring topology is a mirage, due to a configuration known as "collapsed backbone". in this instance, both pairs of fiber ride in the same conduit for some portion of the distance (most notably laterals to building entrances, but sometimes for a fair distance down the street). the driving factor in building this way is usually cost savings. while this arrangement does protect against failures of optics and electronics (which in fairness are indeed more common than fiber cuts), it provides no protection against hungry construction (or in this case, lawn maintenance) equipment. ---rob
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