Extreme Networks has copied Nortel's campaign of attacking the Cisco Energy Tax, but then hides energy consumption behind unreal 'best practices', and creates a closed calculator tool.
Virtually all Extreme's estimated "savings" are based on their assumption that all phones/ports are powered off - every night, weekends and holidays. Basically Extreme's "Green IT" best practices design recommendation is that customers power their network down the equivalent of 106 days out of the year to save electricity. For the vast majority of companies that I talk to this approach does not make either business or operational sense. Reject this best practice and the result is higher energy bills and TCO with Extreme solutions.
Extreme's Energy Savings Estimator is hard coded and hides any of the assumptions used to arrive at the results. Contrast this with Nortel's approach of making all assumptions clearly visible to users of our tool and verifying these through third party testing with open invitations for competitor participation. One analyst I spoke to actually uses the Nortel Energy Efficiency Calculator in a two-day course he runs.
So don't get blind-sighted by Extreme claims ... and demand all the facts.