INTRODUCTION The market for VoDSL loops to provide broadband services is currently experiencing explosive growth as the preferred last-mile deployment method for integrated communications providers in United States. Due to the explosiveness of the Internet and the massive data traffic through network convergence of voice and data technologies, VoDSL came into existence (Franz, 2000). VoDSL service has the capability to provide the customers with converged voice and data, including local and long distance telephone service, in addition to high speed Internet access on a single DSL copper line. The dial-up modem has in the past represented the means of connectivity for on-line access and Internet access. Enterprise systems have since migrated away from 56K dial-up to a faster methodology of communication. This move was necessitated as a result of the extensive copper networks, owned by exchange carriers. As the Digital Subscriber Line (DSL) continues its emergence as the choice of transportation for high speed data over existing telephone lines, enterprise systems are challenged on how to converge and maximize voice calls and high speed data over these same lines (Opara, 2004). As businesses continue to maneuver in the 21st century competitive environments, enterprise systems will thrive for excellence on how their network will remain effective, efficient, and reliable, while maintaining a relatively low overall cost of doing business. This study focuses on the use of the Asymmetric Digital Subscriber Lines (ADSL) technology, because it provides a life-line capability. This means that if there is power loss at any giving time, one telephone line will still be functional. This is because the technology has a lower bandwidth as the system travels upstream as compared to the downstream movement. Further, the technology transmits a high bit rate data in the downwards direction from the central office (CO) to the subscriber (downstream), with typical bit rates from 1.5 to 8 Mb/s, and lower bit rate data in the reverse (up) direction from the subscriber to the CO (upstream), with bit rates from 64 to 640 Kb/s (ANSI 1995). ADSL is used for asymmetric services to residential and small office home office (SOHO) customers. This paper will show outcomes that can be used in evaluating VoDSL solutions that offers multiple voice connections simultaneously with data onto the high speed digital line offered by an ADSL line. The results are based on the V/LQ of VoDSL. After the literature review, we present the description of the network architecture for V/LQ test setup. Then, we have discussions on the subscriber loop plant noise, concludes with the results of the tests performed. LITERATURE REVIEW Andersen (2007) found evidence that asymmetric DSL (also known as ADSL) has gained substantial interest in residential, small and medium size enterprise markets as a convenient way to gain access to high speed internet services. The reason is the continuous drive of enterprise systems toward voice/data convergence with the goal of reducing overall network usage costs. Finweek (2008) reported that VoDSL is a simplified voice solution effortlessly integrating with the provider's existing connection to the PSTN (Public Switched Telephone Network). Earlier studies found that convergence of voice and data in telecommunications is not a new paradigm, however, both ATM and IP or IP over ATM protocols are now used as technologies for convergence networking since both enhances lower network, operational and maintenance cost (Opara, 2004; Galli & Kerpez, 2002). Most recent studies (Andersen, 2007), found evidence that VoDSL technology has a similar architecture to the legendary public switch telephone network (PSTN). The studies summarized by stating that this technology is a promising breakthrough to the so-called next generation networks (NGNs). …
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