Go Green with ASSIA Power Management
posted by Wonjong Rhee
November 29th, 2010
Whether global warming is the real thing or nature’s hiccup, much of the world is determined to develop and use green energy solutions to reduce power consumption and CO2 emissions. Governments and regulatory agencies are leading this effort, which is likely the right direction regardless of the cause of climate change. As part of the overall push to lower power consumption, there is increasing pressure to cut power in telecommunications data centers. One area that many operators are focusing on is improving energy efficiency in their DSL networks. A typical ADSL port consumes 0.5-2 watts of power from the central office side. VDSL ports consume much more. For an operator with 5 million DSLs, the numbers translate into an electricity bill of $2.5M-$10M per year. In fact, a study by Broadband Forum found that a 1-watt saving for telco equipment translates into an overall 2.41-watt savings, taking into account the overhead of power converters and the need for air-conditioning. So the actual final bill could be as high as $6M-$24M per year!
Replacing the existing equipment with the latest green-labeled model is certainly a possibility. However, an easier, faster, and more economic solution is to adaptively control the transmit power of each port so that the minimum power is used for each DSL. (Most of the DSLs use the maximum power allowed because the MAXSNRM feature in the standard is almost always broken or unused.) Using this type of power management tool can result in 0.2-0.5-watt savings per port, which translates into $2M-$6M per year savings for a 5M-line network. The power management function, however, needs to be implemented with great attention to detail and caution because any over-reduction in transmit power can result in a loss of stability or synch rate of the DSL, or both. The proper reduction is different for every single DSL because each DSL is unique. Furthermore, the optimal reduction often varies over time for a single DSL due to the changes in the noise environment, temperature, copper fault, and other network factors. All of these issues can be managed effectively with ASSIA’s DSL Expresse® software, where every single DSL is continuously monitored and optimized to the appropriate power level. In this way, the maximum power savings are achieved while there is virtually no loss in stability and rate performance in the network.