Hybrid Cloud Computing QoS Glitches Lubna Luxmi Dhirani, Thomas Newe Department of Electronic and Computer Engineering University of Limerick Limerick, Ireland. lubna.luxmi@ul.ie, thomas.newe@ul.ie Shahzad Nizamani Department of Software Engineering Mehran University of Engineering and Technology Jamshoro, Pakistan. shahzad.nizamani@muet.edu.pk Abstract—The Hybrid Cloud Computing model has been growing extensively due to its Infrastructure as a Service (IaaS) architecture, customisation and cost benefits. The hybrid cloud services are measured based on the Quality of Service parameters defined by the public cloud vendors. These parameters (i.e. availability, scalability, latency etc.) vary from vendor-to-vendor, developing complexity and confusion on the grounds of methods of service assessments. A Cloud Service Level Agreement (SLA) lists the QoS provisions to be provided to the tenant, the objectives, and exclusions. Regardless of vendors promised uptimes and service metrics, the tenants are susceptible to the following threats: data governance, Denial of Services, multi-tenancy, etc. Cloud computing has often been compared as a utility, but the basic different between a utility and the cloud is the amount of risk involved with data protection, provisioning and control. Few cloud standards have been developed for standardizing the hybrid cloud model but since each public cloud vendor provides different applications and services, these standards do not resolve the existing cloud QoS issue. Since each enterprise implementing the cloud and vendor supplying the services is diverse, a customized Trio (Cloud-IT-Business) QoS model is required to resolve the business need. The authors have designed a model to resolve this existing cloud QoS issue, the abstraction of the model is detailed in this paper. Keywords—Hybrid Cloud computing, Quality of Service, Cloud Computing Standards, Cloud Fishbone. I. HYBRID CLOUD COMPUTING Cloud Computing is an IT-based service provided by different cloud vendors, these services differentiate based on the type of cloud architecture (i.e. public, private, hybrid and community) and delivery models (Infrastructure as a Service (IaaS), Platform as a Service (PaaS), Software as a Service (SaaS), etc.). Clouds computing supports large-scale distributed computing systems built on the key concepts of: computing as a utility, virtualized resources, on-demand computing, etcetera. These concepts have enabled the cloud platform as a promising platform for enterprises to outsource their IT operations [1]. Hybrid Cloud Computing blends two different architectures (public and private cloud) based on cloud tenants demand as shown in Fig.1. Hybrid cloud is majorly utilized by tenants who own on-premises private clouds and develop on- spot computational requirements for data processing. Hybrid cloud supports applications to run simultaneously on two different cloud architectures, eliminating cloud bursting situations or failovers. Fig. 1. Hybrid Cloud Infrastructure QoS. This paper focuses on the Hybrid Cloud QoS issues specifically the cost dimension and is divided into the following sections: Section II discusses the importance of Quality of Service in Cloud, IT and Business. Section III briefs the Cloud Quality Process Improvement and decision making in the cloud, Section IV discusses cloud cost and pricing models. Section V concludes the paper. II. QUALITY OF SERVICE Quality of Service (QoS) is widely used by both IT and commercial service sectors to define accuracy, performance, efficiency, portability, security, etc. QoS is a Total Quality Management (TQM) [2] term and benchmarks an enterprises capability and Key Performance Indicators (KPIs) to measure the delivered QoS. The term Quality has been described differently by various authors as shown in Table I. TABLE I. VARIOUS DESCRIPTIONS FOR QUALITY Quality Attributes [2] Gravin Performance, features, reliability, conformance, durability, serviceability, aesthetics, perceived quality. Parasur aman et al Tangibles, Service reliability, responsiveness, assurance, empathy, availability, timeliness, professionalism, completeness. Wild The QoS is assessed based on customer satisfaction which is subject to design and product quality. Basu Top management commitment, sales and operational planning, using tools and techniques, performance and knowledge management, teamwork culture, self-assessment. QoS has a significant impact on the overall success on any organization as it significantly affects the profit aspect. The total cost of quality is divided into costs associated to failure and controlling the issue. These factors are further categorized