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DSL - Section 3

More detail.. DSL[2] (Digital Subscriber Line) is a generic name for a family of standards allowing high speed data transfer over telephone lines (POTS), otherwise known as twisted pair. For carrying IP, DSL competes with cable modems, satellite digital data feeds, wireless digital data, ISDN, 56k modems and more expensive frame-relay lines etc.
Since the twisted pair lines used in the telephone network that are to carry DSL are not shielded from interference, there are limits on the distance DSL signals can travel before degrading the maximum DSL speeds available in all DSL standards.
This distance limitation of DSL is only one of many potential technical hurdles to pass before an installation is complete.

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The installation of DSL is typically not done by the customer.
Assuming the ordering process is complete, installations typically happen in three phases. The first phase belongs to the phone company after they receive a work order from the DSL provider. It is tough for the customer to ascertain from the phone company the progress of this stage, as they usually do not possess the work order number that the phone company will need to check its systems. Asking the phone company to check status by customer name, or street address, may work, or it may not, depending on how efficient your phone company work dispatch systems are.
In the case where the phone company is the DSL provider, then things are a little simpler.
Normally the first visit, at or near the premises, is by the phone company technician. This may involve inside entry, or they may just need access to the basement, or outside phone equipment box, depending on the type of building.
After this first visit, the DSL provider is informed by the telco that the line is ready to be tested, and then there is a second visit. There can be problems at this stage, since if the phone company is not used to dealing with digital lines, the DSL provider technician may find the line has not been brought far enough into the premise, and for reasons as diverse as risk, lack of blue prints, or plain confusion, it may not be possible for the technician to pull the line up the inside of the home. Assuming it is possible to get the line the telco left, it is then on this visit that any inside wiring is done.
Inside wiring is no more frightening than that which occurs when you order a new phone extension socket... although every case can be tricky. The technician will may also terminate the DSL line on the wall with a special socket. This socket is quite simple - when there is no cable plugged in, a leaf spring comes down and shorts out the prongs. This is used for testing like this: if there is a fault, the DSL provider can ask you to remove your cable and test for cable integrity by doing a loopback test down your line. This will show whether the line has been cut by a back-hoe or a random telco technician while you slept. Note also, once your end of the cable has been found, the network center can do a line length test and measure almost to the foot how long it is. This is helpful to explain why connection integrity is not what is was supposed to be.
One last test the DSL technician can do is a speed test.. they will talk to 'mission control' and ask them to crank up the speed to the max, and check if your router or modem can sync at that speed. It is useful to know your maximum on the line should you want to request faster speeds in future. Do not be disappointed if your 5000 foot line, well under the technical maximum, cannot go faster than 1.0mbps: considering the possible age and oxidation state of the copper it is a small miracle you can get any data down the line at all!
At last, the big moment when the DSL equipment is plugged in and turned on.
The final phase is being able to ping something on the other side of the world. Largely, this is your responsibility, unless you have a very vanilla computer setup, for instance windows98 or windows95, in which case the DSL provider technician can help with the computer configuration process while they are still there.

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