The Year of the Backhoe Continues...

Sean Donelan SEAN at SDG.DRA.COM
Wed Dec 3 20:16:55 UTC 1997

>The relative severity has gone up though for two reasons. First, there
>is more fiber than ever in the ground and that which is in the ground
>is carrying more traffic than it used to. So a single cut can cause
>lots of people problems. Also, because of the increase in internet
>use, the visibility of such cuts has gone way up.

Doesn't any one else get a chuckle when they hear a *single* cut can
cause lots of people problems when referring to the Internet, given
the mythological history of the Internet's design goals?

Looking over logs for the last few years, the same causes why the
application user has problems show up over and over again.  Here they
are in order....

    1. Congestion
    2. Operator/Software error
    3. Telcom facility outage (fiber/cable cut or
         telco 'virtual' service frame/atm/smds/etc failure)
    4. Power failure
    5. Hardware failure

Its difficult to distinguish between operator errors and software
errors, since most cases of operator/software failure often involve
a failure by both.

Also it is sometimes difficult to tell what the true cause of an outage
was.  It may be more convient to blame the usual suspects, than to admit
your own mistakes.  I've noticed some 'fiber cuts' have later turned out
to be switch or DACS programming errors.
Sean Donelan, Data Research Associates, Inc, St. Louis, MO
  Affiliation given for identification not representation

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