Fair greening for DSL broadband access

Given that broadband access networks are an integral part of the ICT infrastructure and that DSL is the most widely deployed broadband access technology, greening DSL has become important. Our recent work demonstrated a promising tradeoff between data rate performance and energy conservation. However, more greening still implies possibly lower data rate, and allocating this "price of greening" across interfering users needs to be fair. This paper proposes four for- mulations of fair greening in interference-limited networks, unifies them into one general representation, and develops a unified algorithm to solve them effectively. Simulations quantify the intuitions on fairness in greening DSL, as these four alternative approaches offer a range of choices between maintaining a high sum data rate and enforcing various definitions of fairness. Fairness of allocating the price of greening is also interesting in its own right.