Consumer-centric resource accounting in the cloud

"Pay only for what you use" principle underpins the charging policies of widely used cloud services that are on offer. Ideally for these services, consumers should be in a position to verify the charges billed to them. However, unlike traditional utility services such as gas and electricity, no consumer--trusted metering services are available for cloud services, so consumers have no choice but to rely on the usage data made available by the providers. In light of this, the paper proposes the notion of Consumer--centric Resource Accounting Models for cloud resources. An accounting model is strongly consumer?centric if all the data that the model requires 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. With this view in mind, the accounting models of some widely used cloud services are examined and possible sources of difficulties in data collection are identified, including causes that could lead to discrepancies between the metering data collected by the consumer and the provider. The paper goes on to suggest how cloud service providers can improve their accounting models to make them consumer-centric.