Why do some locations qualify for DSL, but others do not? Why do speeds vary from location to location?
There are two primary factors in determining availability of DSL to your location. First is related to your Central Office (CO). Every telephone line in the region is connected to one of several centralized “hubs” called Central Offices (CO’s). To make DSL available to an area, the DSL provider must install their DSL equipment inside the CO. If the CO used for you phone service does not have the required DSL equipment, you are out of luck. The second factor is related to line length or quality. In short, the digital signals required to carry DSL service will degrade as the wire between you and the CO becomes longer. The longer the wire, DSL speeds will be slower. The physical length limitation of most DSL service is 15,000 to 18,000 feet. If your phone line is longer than this, you are out of luck entirely. DSL speeds are typically sold as “best effort” because of these technical limitations. For example, you may pay the same for a 1.5 megabit connection than you would 1.0 megabit conn
