On Trustworthiness of CPU Usage Metering and Accounting

Abstract—In the envisaged utility computing paradigm, a user taps a service provider’s computing resources to accom-plish her tasks, without deploying the needed hardware and software in her own IT infrastructure. To make the service profitable, the service provider charges the user based on the resources consumed. A commonly billed resource is CPU usage. A key factor to ensure the success of such a business model is the trustworthiness of the resource metering scheme. In this paper, we provide a systematic study on the trustworthiness of CPU usage metering. Our results show that the metering schemes in commodity operating systems should not be used in utility computing. A dishonest server can run various attacks to cheat the users. Many of the attacks are surprisingly simple and do not even require high privileges or sophisticated techniques. To demonstrate that, we experiment with several types of attacks on Linux and show their adversarial effects. We also suggest that source integrity, execution integrity and fine-grained metering are the necessary properties for a trustworthy metering scheme in utility computing. Keywords-CPU time metering; attack; utility computing I

Reliable Accounting in Grid Economic Transactions

In the Grid computing model a remote service is provided by a resource owner to a client. The resource owner executes a client job and charges the client for a corresponding fee. In this paper we discuss the main weakness of many existing models for performing such a kind of transaction, i.e., the strong assumption that both the resource owner and the clients are honest. Then, we propose a new security model in which either the resource owners or the clients (or both) may not be honest. Our model introduces a trusted third party, referred to as "Grid Manager". We describe in details the role of the Grid Manager and argue the advantages of our proposal with respect to the current state-of-the art. © Springer-Verlag 004