Locations with no good Internet

I don't know about anything other than Qwest-land in Arizona, but we are seeing the few T1s that are still in service provisioned as you described: a 2-wire DSL connection, although not out of a local DSLAM.

I think it depends on your definition of the box that's being used for connections as a DSLAM. It's certainly not the same traffic engineering as DSL, because DSL circuits are muxed at the DSLAM (at least in Qwest-land) and may or may not be subject to congestion when leaving the neighborhood remote terminal DSLAM. We for sure NEVER see any congestion on the T1s that are being provisioned using DSL technology.

Now, whether that's the same chassis with engineering over an uplink, or two separate chassis in the same road-side wart for the two different services, that's a deployment issue.

In other words, I think you're right about the technology involved (DSL-ish 2 wire circuits) being used to deliver, but there's more to it than repair time SLA when it comes to selling the same 2 wires as DSL for $39.95 and T1 for $399.95. (again, at least out here in the Wild West)

That being said, I think your fundamental point is likely correct, something well known to everyone in this business: the cost to a Telco to provide T1 service is not 10x the cost to provide DSL service at similar speeds, and when there is that much additional marginal revenue being generated, they are going to fight with politics, tariffs, and any other tool at their disposal to keep the additional revenue coming in as long as possible.

jms

For a T1 it's a "smart jack" on each end (and often repeaters in the
middle) that have been engineered to run an HDSL signal between them
and a classic T1 signal "outward" from each end. One independent set
per T1; they aren't aggregated until after they're converted back to a
classic T1 signal.

http://en.wikipedia.org/wiki/Network_interface_device#Smartjack
http://help.trixbox.com/Troubleshooting/What_is_a_Smart_Jack%3F

The major difference between using HDSL smart jacks and classic smart
jacks is that the HDSL ones don't need wire that's in quite as good
shape and they don't need repeaters between you and the CO as often.
They're still very much a T1 service.

Regards,
Bill Herrin

Here in Maine, they use HDSL (two pair) to supply T1. They put repeaters down the line or work it out of a SLICK. The bridge taps and side taps are removed from the loops (conditioned) and then there's the SLA. I learned to always have a spare CSU/DSU on site.

--Curtis