ADSL loop extender

Abstract: A public switched telephone network (PSTN) provides digital video signals from a video information provider or digital service bureau to one or more of a plurality of subscriber premises. Administration of orders from subscribers is carried out by a video gateway and file servers at the central office. Asymmetrical digital subscriber line interface (ADSL) units over a local loop carry the necessary signalling between the subscribers and information providers. The interface units frequency multiplex digital video information with voice information to the subscriber and support transmission of a reverse control channel from the subscriber to the central office for transmission back to the information provider. Several enhancements and special features are disclosed.

Abstract: A public switched telephone network (PSTN) provides communication of digital data from a data provider or LAN to one or more of a plurality of subscriber premises. Asymmetrical digital subscriber line interface units operating at variable rates and in variable modes (ADSL/AVRs) over a local loop offer one-way video-on-demand and other services and carry the necessary signalling between the subscribers and information providers. In an asymmetric mode, the interface units frequency multiplex digital information with voice information to the subscriber and support transmission of a reverse control channel from the subscriber to the central office for transmission back to the information provider. Other modes are supported which permit selective bi-directional and reversible communications as well.

Abstract: This standard presents the electrical characteristics of the Asymmetric Digital Subscriber Line (ADSL) signals appearing at the network interface. The physical interface between the network and the customer installation is also described. The transport medium for the signals is a single twisted-wire pair that supports Plain Old Tephone Service (POTS) or voiceband data services and high-speed duplex (simultaneous two-way) and simplex (from the network to the customer installation) digital services. This interface standard provides the minimal set of requirements for satisfactory transmission between the network and the customer installation. Equipment may be implemented with additional functions and procedures. Approval of an American National Standard requires review by ANSI that the requirements for due process, consensus, and other criteria for approval have been met by the standards developer. Consensus is established when, in the judgement of the ANSI Board of Standards Review, substantial agreement has been reached by directly and materially affected interests. Substantial agreement means much more than a simple majority, but not necessarily unanimity. Consensus requires that all views and objections be considered, and that a concerted effort be made towards their resolution. The use of American National Standards is completely voluntary; their existence does not in any respect preclude anyone, whether he has approved the standards or not, from manufacturing, marketing, purchasing, or using products, processes, or procedures not conforming to the standards. The American National Standards Institute does not develop standards and will in no circumstances give an interpretation of any American National Standard. Moreover, no person shall have the right or authority to issue an interpretation of an American National Standard in the name of the American National Standards Institute. Requests for interpretations should be addressed to the secretariat or sponsor whose name appears on the title page of this standard. CAUTION NOTICE: This American National Standard may be revised or withdrawn at any time. The procedures of the American National Standards Institute require that action be taken periodically to reaffirm, revise, or withdraw this standard. Purchasers of American National Standards may receive current information on all standards by calling or writing the American National Standards Institute. American National Standard

Abstract: From the Publisher: The only book on the market that deals with ADSL technologies at this level, Digital Subscriber Lines: Toward, Above, and Beyond ADSL is ideal for computing professionals who are looking for new high-speed communications technology, who must understand the dynamics of ADSL communications in order to create compliant applications, or who simply want to better understand this new wave of technology. Includes calculation examples for all signal environments Covers ADSL and a multitude of other xDSL technologies Compares and contrasts ADSL to current MODEM-based technologies