ADTRAN 600 Series user manual Voice Over DSL Overview

Total Access 600 Series SHDSL IAD User Interface Guide/64200683L1-31B

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2.VOICE OVER DSL OVERVIEW

Voice over DSL (VoDSL) refers to providing toll quality voice access to the Public Switched Telephone Network (PSTN) over twisted copper pair using DSL. Data can be combined with multiple voice lines over a single medium via DSL, thus yielding many advantages over traditional TDM technologies.

Traditional TDM technologies are limited by statically allocating bandwidth. DSL overcomes this by providing a large bandwidth and utilizing other technologies, such as ATM, to dynamically assign bandwidth as it is needed. Because of this, the user is able to add voice and data connections over a DSL line with flexibility and ease.

3.VOICE OVER ATM OVERVIEW

Voice over ATM is the technology used to transmit voice conversations over a data network using Asynchronous Transfer Mode (ATM). There are several potential benefits to moving voice over a data network using ATM. First, the small, fixed-length cells require lower processing overhead. Second, these small, fixed-length cells allow higher trans- mission speeds than traditional packet switching methods.

ATM allocates bandwidth on demand, making it suitable for high-speed connection of voice, data, and video services. Conventional networks carry data in a synchronous manner. Because empty slots are circulating even when the link is not needed, network capacity is wasted. ATM automatically adjusts the network capacity to meet the system needs.

4.VOICE OVER DSL APPLICATION

The Total Access 600 connects to a DSLAM via DSL and ATM. The Total Access 600 has a built in echo canceller that provides G.165 echo cancellation. The module can automatically detect ADPCM and enable it as needed.

Figure 2 shows a typical VoDSL application. The Total Access 600 connects to the ATM network, via a DSLAM, to provide both voice and high speed data from a single platform.

© 2002, ADTRAN, Inc. Total Access 600 Series User Manual