The fact of the matter is, no one really knows how many minutes a year the telephone network doesn't work. Or, if anyone knows, they aren't telling.

In the course of preparing this month's cover story, it became abundantly clear to me that network reliability is a slippery concept — there are no established guidelines by which to calculate availability figures.

For example, not all cable operators define an "outage" in the same manner. Telephone companies don't consider the loss of commercial power an outage, because it's not their fault. Furthermore, the telcos don't even acknowledge there is an outage until they receive a phone call to report it.

Interestingly, the telecommunications industry does have a working group that has been investigating network survivability and performance. Established by the FCC after a fire in a New Jersey central office took down a huge number of phones for several hours, the group has been toiling on two projects designed to quantify and classify network outages.

In its work, the group (known as the T1A1.2: Working Group on Network Survivability Performance) developed an arithmetical formula to calculate outage indexes and other reportable criteria so that it could inform governmental agencies how the nation's telephone networks are performing.

The group's stated goals are admirable, but instead of taking raw data and simply plugging it into the formula, phone companies are instructed to weight the outage by when it occurs and how many people it affects. For instance, an outage isn't an outage unless it affects 30,000 people or more. An outage is also only one-tenth of an outage when it occurs between 11 p.m. and 8 a.m., because fewer people use the phone then.

The result is, predictably, a much rosier picture than it otherwise might be. It's debatable that such an outage index is even meaningful. Instead of figuring out what caused the outage, the phone companies seem bent on putting a positive public relations spin on the whole thing. Rather than getting out the microscope to understand outages, this working group would rather spot problems with binoculars and talk its way out of blame before the bomb hits.

A Bellcore official recently presented this work to a group of cable TV engineers, begging for cable participation in the panel's work. Instead of taking the bait, the engineers hammered the Bellcore rep on the group's motives. As well they should have.

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