research opportunities in DSL standards

The continued growth of multimedia traffic pushes access network operators to further boost performance over their copper infrastructure network. As a result, digital subscriber line technology has evolved substantially. Field trials have proven that recent innovations, such as crosstalk cancellation and phantom mode transmission, can push data rates of Very high speed Digital Subscriber Line (VDSL2) above 100 Mb/s on a single twisted pair and above 300 Mb/s on two pairs. At the International Telecommunication Union (ITU), a new access technology to provide aggregate data rates in the range of 500 Mb/s to 1 Gb/s per copper loop of up to a few hundred meters is being defined in the G.fast project. G.fast enables the continued cost-effective deployment of fiber in the access network. In this paper, we give an overview of some key research challenges that need to be addressed for this new access technology to become a success. We show how innovation is essential throughout the entire life cycle of a technology.