Both Cisco and Juniper are backing the Alliance for Telecommunications Industry Solutions' Telecommunications Energy Efficiency Rating specification, which ATIS introduced last year.
However, neither specification has been universally accepted. Juniper supports ECR but doesn't include the rating on all of its products' data sheets. Cosgro says HP hasn't included either of those energy-efficiency standards in its data sheets because users don't understand the metrics.
"What they care about is the number of watts used," he says.
Another strike against the specifications, Cosgro says, is that they lack a detailed, open rating methodology. That means vendors can choose rating firms that use methodologies that best suit their needs.
A truly open specification isn't likely to appear until next year at the earliest, when the Environmental Protection Agency starts work on an Energy Star rating for large networking equipment.
The agency announced an Energy Star specification for data centers in June and plans to eventually develop specifications for data center UPSs and cooling systems, according to a spokesman. These new specifications, which will cover everything from power supplies and internal chips to Energy Efficient Ethernet, will be "the key energy-efficiency standard" going forward, Cosgro says.
The easiest way to increase energy efficiency is to buy new equipment, but that's not necessarily a practical option, because network administrators making purchasing decisions must consider other factors besides potential energy savings -- such as the remaining useful life of their current equipment. A 15% cut in energy costs may add up when spread across thousands of servers, but the total savings would be much smaller on a few racks of switches.
Even for a single rack, the cost per kilowatt usually won't justify an upgrade. "Most people will not save enough energy in the short run to justify replacing their equipment," warns Burton Group's Reeves. "Stay on your regular life cycle."
5 Ways to Green Your Network
1. Refresh your equipment. Cisco estimates that the energy efficiency of its products improves 15% to 20% every two to three years. The energy savings alone aren't enough to justify buying new equipment, but improving efficiency is one of several reasons for keeping your refreshes on schedule.