DSL Advances

4.2. Second-Generation HDSL (HDSL2)

The primary goal of second-generation HDSL, hereby referred to as HDSL2, is to utilize the advancements in integrated circuit design to develop a digital subscriber line transmission system that transports a DS1 payload on a single wire pair on loops that meet carrier serving area (CSA) requirements. This objective has the same deployment coverage as conventional HDSL that uses two wire pairs. Figure 4.13 shows a provisioning diagram of a T1 access circuit provisioned using second-generation HDSL technology. Although the core technology for the transceivers is more complex than that for first-generation HDSL, the total provisioning and equipment costs will be lower than for conventional HDSL when deploying ...