5963 computer grade dual triode production dates 3503

Sure, but "in major toll centers" is *very* limiting, because the advantages of SS7 were only realized when it was extended to the Local Exchange Carriers. Given that the first full implementation (by Sprint) for a toll network was in 1988 (and AT&T very shortly after that), there had been no incentive for LECs to implement SS7 *until* 1990. In fact, many of them were still using non-digital switching systems that could not make use of SS7.

The real import of SS7 was not available until *after* 1990, and it was rather rapidly adopted between then and 1995.

Exactly. And it wasn't until *that* was complete before the LECs could actually make use of it.

Not by the SS7 deployment of the IXC's! But they were certainly affected between 1990 and 1995 by the mbuttive move of LECs to SS7.

Yes... the *late* '80s. But note again that you are considering only Long Distance (4ESS etc.), not line switching by LECs.

True for the quality of transmission characteristics. But of course there are other measures of "quality", and some of them *do* matter to "dumb consumers". Price of course is a major factor. Availability is another. What you have listed are measures of only the transmission quality. But we knew very well even in the 1930's (when the Telecommunications Act essentially allowed a set of standards which were a target was recommended, not required) that customers who with horrible service over barbed wire fence... were very happy to just *have* a telephone. This isn't something new, caused by cell phones...

I've spent a great deal of time studying how and why a NOC functions the way it does (or doesn't), in efforts to design better trouble ticketing systems.

Trust me, there is a *huge* amount of what is going on that we don't know. Remember back when every switch was maintained by a crew that had at least a few old switchmen... and they used to be so tuned to what the switch *sounded* like, that when they heard an unusual noise they set about to figure out what was wrong? We don't have that level of familiarity with the switching systems anymore.

I wrote software to analyze log reports at the Fairbanks Toll Center back in the early 1990's. This is a topic that I have more than a casual introduction to. The biggest problem is spotting unique troubles that are *not* trends. For example, a digit receiver that drops the number every 5th time it is used... will most likely *never* be discovered. From a signal device, the numbers are not high enough to trigger anyone's attention. If the device itself does not go into alarm, it will continue to dump call forever.

Ha ha, you think AT&T is any better????

AT&T is so hung up on how to administer the operations of a large company that they can't *operate* any given small part of it effectively. The result is an "efficient" top level, managing a large number of ineffective (hence not profitable) operations.

Basically they can't implement anything in any part of the company unless it is something that can be done company wide in an efficient manner.

We can find just as many isolated incidents of AT&T being just as confused. Ask someone why they have both a 4ESS *and* a DMS-200 in the Anchorage Toll Center...

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