xDSL chips provide digital subscriber line (DSL) connectivity in a system-on-chip platform. The term xDSL refers collectively to all types of digital subscriber lines. An xDSL chip is a generic term for all forms of DSL service spanning transmission speeds from 128 kbps to 52 mbps. DSL service connection takes place between equipment of the subscriber and the telephone exchange. A protocol is used between the exchange and an internet service provider. A broadband DSL enables the delivery of services at higher data rates and enhances the value for the individual or corporate user. Selection of the DSL provider is based on a combination of a number of factors such as price, dependability and service, DSL hardware, email accounts, and networking. DSL router chips enable connections of shared communication between different computer equipment where computers attached to the shared routers can access the same printers, files, or an internet connection. There are many types of xDSL chips. Examples include SDSL, HDSL, and ADSL. SDSL is a single-line version of HDSL, transmitting T1/E1 signals over a single twisted pair, and able to operate over the plain old telephone service. HDSL is simply a better way of transmitting T1/E1 over copper wires, using less bandwidth without repeaters. It transmits two separate data streams with much more bandwidth devoted to the downstream leg to the customer than returning. ADSL provides greater volume of data flow in one direction. Its downstream rates start at 256 kbit/s and typically reach 8 Mbit/s within 1.5 km. Other xDSL chips are commonly available.