I find the example in the conclusion simplistic and somewhat flawed. I am a strong advocate of the Business Risk Assessment in the determination of high availability design and assume that the balance-sheet approach described addresses that as well. But to conclude that dual-cording does not improve reliability because the external power source has no redundancy ignores other factors internally that provide the second source such as: on-site generation, redundancy in the infrastructure — double-ended substations, dual/redundant UPS etc.
Howard Levison
levisonh@cs.com
Re: Fundamentals of the post-boom Internet data center 3/1/02
