3Com has claimed it leads the market in making its networking gear more energy efficient. The company based its claim on a report by US analyst firm In-Stat; however, a rival has charged that 3Com only counted its role in enterprise-class large switches and may actually lag behind in greening the key market for small and mid-sized Ethernet switches.

According to the report, Green Networking Equipment: Who Leads and Who Lags, LAN switches from 3Com are up to 60 percent more energy efficient than those from its competitors. 3Com added that its newest products are also up to 78 percent more efficient than its previous ones.

The advantage comes from having a more up-to-date product range, argued Steve Johnson, 3Com's UK channel manager. "The acquisition of H3C gave us the opportunity to refresh our entire enterprise LAN portfolio with products that were designed with power in mind," he said.

In-Stat senior analyst Victoria Fodale said that the report took vendors' published specifications, and calculated how many Gbit/s of backplane capacity their switches claimed per Watt consumed.

"We found significant differences in energy consumption among apparently similar networking products," she said. "One Ethernet port can consume more than ten times as much as another."

According to the report, the energy efficiency leaders included 3Com, Force10 and Netgear, while vendors such as Cisco, Foundry, HP ProCurve and Nortel were towards the bottom of the rankings.

However, by focusing on campus switches the report passed over the huge volume of Ethernet ports sold into smaller organisations, according to Chris Davies, the UK general manager of D-Link.

"Manufacturers also rate their products differently," which makes them hard to compare, he said. He claimed that while everyone is working on energy efficiency, only D-Link has implemented specific power-saving technologies, such as powering-off unused ports and compensating for cable length.

I'm delighted another manufacturer is bringing Green onto the agenda," he added. "But product for product, I estimate we're saving up to 50 percent compared with 3Com."

Fodale acknowledged that the report's methodology "was pretty simple", and said it would be improved in future reports. She said that the most important thing was that it had got vendors and users alike talking about the issue of energy efficiency.

She noted that at the moment, power efficiency "hinges on the components - are they using standard components or proprietary components? Off-the-shelf silicon has progressed faster than proprietary, but big enterprise vendors such as Cisco and HP ProCurve tend to use proprietary ASICs for differentiation."

Some ASICs are still being made on 130nm manufacturing processes, she noted, but merchant chip suppliers such as Broadcom have moved fast to 65nm, producing smaller chips that consume less power.

3Com's Johnson added that technology can help organisations reduce their carbon footprint in more ways than simply making the hardware more energy efficient. For example, 3Com's OSN (open services networking) initiative allows third-party applications which would otherwise need their own hardware to run on its routers.

"OSN can reduce the number of standalone appliances and the amount of rack-space and cooling needed," he said. "There is also the innovation that enables customers to change behaviour, such as using collaborative technology to reduce business travel."

Read Bryan Betts' related blogpost, where he asks if Carbon is now the Hoover of the environment.