A Case for Consumer–centric Resource Accounting Models

A pay-per-use cloud service should be made available to consumers with an unambiguous resource accounting model that precisely describes all the factors that are taken into account in calculating resource consumption charges. The paper proposes the notion of consumer-centric resource accounting model such that consumers can programmatically compute their consumption charges of a remotely used service. In particular, the notion of strongly consumer-centric accounting model is proposed that requires that all the data needed for calculating billing charges can be collected independently by the consumer (or a trusted third party, TTP); in effect, this means that a consumer (or a TTP) should be in a position to run their own measurement service. Strongly consumer-centric accounting models have the desirable property of openness and transparency, since service users are in a position to verify the charges billed to them. To illustrate the ideas, the accounting model of a given cloud infrastructure service (simple storage service, S3 from Amazon) is evaluated. The exercise reveals some shortcomings which can be fixed as indicated in this paper to make Amazon´s model strongly consumer-centric. Service providers can learn from this evaluation study to re-examine their accounting models and perform any amendments.