Continuous and Distributed Monitoring of Cloud SLAs Using S3LACC

Abstract

Cloud services are contracted by a service level agreement (SLA) between a cloud service provider (CSP) and a cloud service user (CSU) which contains quality of service (QoS) parameters, guarantees and obligations. After successful negotiation process, next major task is to monitor the cloud services for ensuring the quality of service according to the agreed SLA. A CSU/company acquiring a cloud service may has requirement of using the cloud service at multiple locations. Manually monitoring a cloud service at different locations and to control the number of communications of SLA violations to the monitoring coordinator (a person/entity that manages the SLAs) requires high level of precision and accuracy. The margin between an acceptable level of service and a violation can be very small in some cases requiring an automated monitoring approach to capture the violations meticulously. In this paper, a distributed monitoring approach is presented for cloud SLAs which is suitable for the cloud services with multiple locations usage. The proposed approach reduces the number of communications of SLA violations to a monitoring coordinator by limiting the unnecessary communications. The decoupled nature of this approach makes it adaptable for multiple locations without any inter-location correlation. A monitoring simulation program is also presented in this paper to validate the proposed monitoring method. Experimental results enforce the effectiveness of our approach and its suitability specifically for distributed cloud SLA monitoring.