- More modular application-specific integrated circuit (ASIC) designs that allow switches to turn off components not in use, from LED panel lights to tables in memory.
- General advances in silicon technology will minimize current leakage and gradually boost energy efficiency with each new generation of chips. Eventually, says Cosgro, "we should be able to get networking equipment that uses 100 watts today down to 10 watts."
- The development of more efficient software that consumes fewer CPU cycles -- and less energy.
- Equipment designs that run at higher operating temperatures to reduce cooling costs.
For example, Cosgro claims that HP's current ProCurve equipment can run safely at temperatures up to 130 degrees -- higher than the specifications for most other data center equipment. "That's driven by requirements of IT managers who want to run data centers at higher temperatures," he says.
Higher operating temperatures may work in a single-vendor wiring closet, but network equipment vendors will need to do a better job of testing in mixed environments before temperatures approaching 130 degrees can be sustained -- especially within racks in the data center. "No one knows how networking and other types of equipment will react when sitting next to servers that displace more BTUs," says Drue Reeves, an analyst at Burton Group.
Today, each vendor tests with only its own equipment.
Another focus: improvements in power monitoring, and management with more granular controls. Real-time power and temperature monitoring is key to any data center and is essential for managing growth. "If something is not right, you want to know about it before a catastrophe happens," says Rockwell Bonecutter, global lead of Accenture's green IT practice.
Management software could be configured to identify specific network equipment, such as VoIP phones, by using the Link Layer Discovery Protocol. The software could then automatically shut off Power-over-Ethernet current for those VoIP handsets at a specific time of day or when the associated PC on each desktop is turned off at day's end.
Another example: Edge switches are typically connected to two routers for redundancy during the daytime, but the network could be configured such that one router goes into a low-power sleep mode at night. The second router would "wake up" only if and when it was needed.
These types of applications represent "a huge opportunity for savings," says Cosgro.
Better specs and standards
Emerging standards could soon help save energy during periods when networks sit unused and will help IT compare the relative efficiency of competing products.
Energy Efficient Ethernet
The emerging IEEE P802.3az Energy Efficient Ethernet (EEE) draft standard may offer the biggest bang for the buck by cutting power consumption for network equipment when utilization is low. Today Ethernet devices continuously transmit power between devices, even when network traffic is at a standstill. Equipment supporting the EEE standard will send a pulse periodically but stay quiet the rest of the time, cutting power use by more than 90 percent during idle periods.
In a large network, that's "a whole lot of energy" that could be saved, Cosgro says.
The standard will allow "downshifting" in other modes of operation as well. In a 10Gbit switch, for example, individual ports that are supporting only a 1Gbit load will be able to drop power down from 10Gbit/sec. to what's required to support a 1Gbit/sec. configuration, saving energy until activity picks up again.
Products built to support the EEE standard should start appearing by 2011, says Aldrich.