Conventional wisdom holds that the vast majority of energy savings in the data center will come through server virtualization, followed closely by more efficient storage and streamlined network infrastructures coming in a distant third.

But new research is suggesting that there may be more to network consolidation and I/O virtualization than meets the eye.

This white paper from Voltaire claims to lay out a strategy to cut overall energy bills in half by unifying disparate network elements and infrastructures into a consolidated fabric. The goal, according to Voltaire, is not necessarily to reduce the amount of energy that network resources consume over a given period, although that helps, but to increase network capacity under the same power footprint. The paper offers tips on deploying power-efficient networks, consolidating server I/O and eliminating bottlenecks and enhancing server virtualization.

Many of the latest power-saving technologies focus not so much on reducing power draw, but making more efficient use of the energy that is consumed. This article describes Blade Network Technologies' RackSwitch Network Virtualization system that streamlines I/O traffic across the blade chassis and racks. The company also promotes a more standardized blade infrastructure that provides for improved energy consumption and management capabilities.

Of course, when it does come to selecting the most energy-conscious network gear, you should know that not all systems are created equal. In-Stat surveyed the leading platforms and found that 3Com's 24- and 48-port switches can be 60 percent more efficient than other devices on the market. In-Stat's analysis showed that 3Com delivered about 3.25 Gbps per watt in 24-port fixed Gigabit Ethernet Layer 2 and Layer 3 environments, compared to a maximum of 2.0 Gbps per watt for other switches. At 48-ports, 3Com was the only firm to hit 2.0 Gbps per watt.

There is still some dispute, though, as to exactly how to measure energy efficiency in network equipment. Groups like Miercom and Tolly Group also offer green ratings, but there are no industry standards with which to make solid comparisons. Support for a more unified system is likely to gain momentum now that virtually every manufacturer in the enterprise is touting one form of "greenness" or another.

In the meantime, it's hard to go wrong with any kind of virtualization/consolidation program, whether it's in the server farm, storage racks or on the network. The trick is to make sure all three elements proceed in tandem to make sure efficiencies in one area don't lead to bottlenecks in another.