DSL Internet Services, or (Digital Subscriber Line Internet Services) are a technology that allow high speed internet service to be provided through traditional phone lines. As such, local phone and telecom companies typically offer this service.
DSL services typically provide downloads ranging from 3 Mbps to 50 Mbps (Megabytes per second). Uploads are generally about twenty percent of the maximum download speed as service providers purposely throttle back uploads to prevent customers from running high load servers or file sharing on their lines. This type of high speed service is technically called Asynchronous (ADSL), and is the most common type of service offered. Many larger centers are now serviced by high speed fiber optic networks and DSL plans with speeds of up to 150 Mbps are now available from some providers. In areas with fiber optic infrastructure, providers may also offer fiber optic service directly into the home and offer speeds of up to 1000 Mbps. Fully fiber optic internet services are discussed in a seperate article here: Fiber Optic Internet
DSL Internet Services can be installed using existing lines, but the provider's technician will often install a new line for the service since many houses have older phone line wiring that is incompatible with newer technologies. Your provider's DSL "Modem" connects to your your computer using an Ethernet or USB cable. Most companies now offer all-in-one devices that act as a wireless home networking access points and routers, and may also act as digital TV boxes.
Generally $25.00 to $55.00 per month depending on the maximum speed offered. High performance fiber optic internet plans may cost $25-$300 per month or more. "Lite" services can also be found in the $15.00- $20.00 range, but these are not suitable for "high bandwidth" activties such as video streaming or online gaming. Some Internet access companies will ask you to buy the equipment (a high speed "modem" and ethernet card, if necessary). Some will ask you to rent it. Some will simply give it to you (returned to them if you cancel). Some providers offer to buy back the equipment if you cancel - some do not. Confused yet? Be sure to ask the provider when you call or read the fine print when applying online.
Most companies offer discounts on high speed internet service when the customer is subscribed to a bundle of services including digital television and phone services.
DSL performance is dependent on your physical distance from the high speed internet provider. If your home is on the edge of the the serviceable area, performance may be poor or reduced. Be sure to fully test your service before the service provider's technician leaves. Many companies now offer DSL equipment with integrated wireless or wired home networking eliminating the need for a separate router or other networking equipment.
Be sure to evaluate all options before choosing your high speed internet provider.