The question on whether public cloud infrastructure is cheaper than running on-premises data centers keeps coming in client inquiries. Clients realize that most of the answers produced by the industry so far are skewed by the vested interests of whoever is coming up with those answer. Public cloud providers make their offerings look significantly more cost-effective than on-premises data centers. Hardware vendors promote the opposite view. Furthermore, within organizations themselves, internal politics continues to inevitably influence the results of any attempt to produce defensible calculations.

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The research states that “cloud services can initially be more expensive than running on-premises data centers. [However, it also proves that] cloud services can become cost-effective over time if organizations learn to use and operate them more efficiently.” The statement is backed by an example of workload migration for 2,500 virtual machines from an on-premises data center to Amazon Web Services EC2. The example TCO (shown in Figure 1) shows an initial uptake in cloud costs and a steady decline as soon as organizations learn how to apply cost optimization best practices (as described in this other framework). The chart also shows how on-premises costs may have a long tail as organizations take time to actually shut down their data centers.

Continue at source : Gartner.com