Proof of violation for response time auditing in cloud systems

In this paper we propose to employ the concept of proof of violation (POV) for the response time auditing in the cloud. A POV scheme enables a user or a service provider to produce a precise proof of either the occurrence of the violation of properties or the innocence of the service provider. POV schemes are solutions for obtaining mutual nonrepudiation between users and the service provider in the cloud. To the best of our knowledge, it is the first scheme that can perform response time auditing according to cryptographic evidences without the need of a delivery agent. Experimental results are presented that demonstrate the feasibility of the proposed scheme. Service providers can use the proposed scheme to provide a mutual nonrepudiation guarantee for response time in their service-level agreements.