On Tue, 25 July 2000, Danny McPherson wrote:

...

Of course, the usual failure mode is backhoe fade, not electronics. In which case, that APS circuit was cut along with the rest.

Of course, backhoes don't normally work inside PoPs, which is the application of APS I was referring to. Routers do fail though (often more than links), and APS has been demonstrated to work relatively well for protecting against such failures.

Although backhoes are often publically identified as the cause of problems, it turns out 71% of the reportable telephone outages last quarter were due to problems inside the carrier's control (i.e. inside the C.O.) according to ATIS/NRSC's calaculations. CO's are dangerous places for network equipment.