Why is distance important with DSL ?
With DSL technology, the distance, or the length of the line between your location and the telco office, is a very important factor in whether or not you can get DSL, and what speed you can get.
The higher the distance between you and the telco exchange, the lower tier DSL service you can achieve.
Generally, the maximum ADSL distance is about 15000 feet for 1Mbit/s, ~12000 feet for 2 Mbit/s service. For IDSL, this range can be extended up to ~27000 feet. This can vary depending on copper quality as well.