Data Centers have been referred to as the SUVs of the IT world. Certainly, these centers have quite demanding energy requirements. However, they are critical to the operation of many IS organisations. The trend towards outsourcing the hosting of software and equipment is unlikely to change any time soon as the business case is well established. Further, the demand for storage is unlikely to abate given the ever expanding digitalisation of media such as music, movies and books. The strong financial results of storage hardware providers such as EMC (http://www.emc.com) in what is a very challenging economic environment are testament to this. At the same time however, any initiative that can reduce power is clearly of benefit. How then can WSNs assist Data Centers in better managing their energy needs?

A Data Center houses IT infrastructure. The infrastructure can range from PC Servers to telecommunications equipment. Software applications, Websites, Files, Databases and Data Warehouses are all hosted on this equipment. The volume of equipment in an average data center is vast and there are key challenges in terms of centers running out of space and in terms of energy costs. However, a 2007 study by Symantec (http://www.symantec.com) has found that while 75% of study respondents are interested in making their centres more 'green' only 1 in 7 has actually achieved this. Respondents also cited the need to balance environmental concerns with business costs. From a data center manager's perspective the 'greening' of the data center is another layer of complexity that will have to be managed.

One of the solutions that respondents are examining is the use of power management products. In fact, 77% of respondents are at least examining the use of power management products for their data centers. Clearly, power management is an area where smart sensors can monitor energy usage and take action in terms of load balancing through the management of this usage data by Vertoda.

Another area that is of issue is heat within data centers. Microsoft (http://www.microsoft.com), for example, established their European Data Center in Dublin, Ireland specifically because the country's mild, temperate climate would reduce cooling costs. Cooling is perceived as expensive for data centers but a 2008 experiment by Intel (http://www.intel.com) found that the failure rate for 450 blade servers in an  data center using tradtional air conditioning was 3.83%. Another section of the data center used an air economiser which simply sucked out hot air and replaced it with outside air with adjusting for temperature and humidity.  However, despite the air being uncooled, the failure rate in this instance was only 4.46%. Intel has estimated that power consumption could be cut by 67% and costs savings of US$2.87 million could be made per annum if this result is extrapolated to a 10 megawatt data center. Intel claims that air economisers can significant reduce its environmental footprint and lead to less power and water consumption.  Typically, data centers use water towers as part of evaporative cooling - with an economiser, potentially up to 76 million gallons of water could be saved in a 10 megawatt data center.

So what role can WSNs play in data centers? Clearly, smart sensors are ideal for monitoring consumption so data centers will know exactly how much they are consuming, be it water or energy. The monitoring of temperature and humidity is key for data centers. Smart sensors, with their small footprint, are ideal for taking these metrics. Maintaining optimal temperature and humidity can avoid unwanted downtime. According to the Gartner Group (http://www.gartner.com) the average cost of hourly downtime for a computer network is estimated to be US$42,000.The lifetime of systems and equipment can be lengthened by providing timely temperature and humidity data within a data center.

The solution that many data centers use for the issue of system reliability is to operate their air conditioning HVAC system at its maximum possible power. This is expensive in monetary and environmental terms. By using WSNs to monitor temperature, humidity, air flow and power consumption data centers can both reduce their costs and enhance their environmental credentials.

Of course, the data provided by WSNs for data centers will need to be reported and used to operate equipment. Vertoda, in conjunction with actuators and WSNs, can provide data centers with a solution that provides timely environmental information to enable data centers to take manual or automated decisions for managing their energy consumption.