Cloud Multi-Tenancy: Issues and Developments

Cloud Computing (CC) is a computational paradigm that provides pay-per use services to customers from a pool of networked computing resources that are provided on demand. Customers therefore does not need to worry about infrastructure or storage. Cloud Service Providers (CSP) make custom built applications available to customers online. Also, organisations and enterprises can build and deploy applications based on platforms provided by the Cloud service provider. Scalable storage and computing resources is also made available to consumers on the Clouds at a cost. Cloud Computing takes virtualization a step further through the use of virtual machines, it allows several customers share the same physical machine. In addition, it is possible for numerous customers to share applications provided by a CSP; this sharing model is known as multi-tenancy. Though Multi-tenancy has its drawbacks but however, it is highly desirable based on its cost efficiency. This paper presents the comprehensive study of existing literatures on relevant issues and development relating to cloud multitenancy using reliable methods. This study examines recent trends in the area of cloud multi-tenancy and provides a guide for future research. The analyses of this comprehensive study was based on the following questions relating to recent study in multi-tenancy which are: what is the current trend and development in cloud multi-tenancy? Existing publications were analyzed in this area including journals, conferences, white papers and publications in reputable magazines. The expected result at the end of this review is the identification of trends in cloud multi-tenancy. This will be of benefit to prospective cloud users and even cloud providers

Software-Defined Cloud Computing: Architectural Elements and Open Challenges

The variety of existing cloud services creates a challenge for service providers to enforce reasonable Software Level Agreements (SLA) stating the Quality of Service (QoS) and penalties in case QoS is not achieved. To avoid such penalties at the same time that the infrastructure operates with minimum energy and resource wastage, constant monitoring and adaptation of the infrastructure is needed. We refer to Software-Defined Cloud Computing, or simply Software-Defined Clouds (SDC), as an approach for automating the process of optimal cloud configuration by extending virtualization concept to all resources in a data center. An SDC enables easy reconfiguration and adaptation of physical resources in a cloud infrastructure, to better accommodate the demand on QoS through a software that can describe and manage various aspects comprising the cloud environment. In this paper, we present an architecture for SDCs on data centers with emphasis on mobile cloud applications. We present an evaluation, showcasing the potential of SDC in two use cases-QoS-aware bandwidth allocation and bandwidth-aware, energy-efficient VM placement-and discuss the research challenges and opportunities in this emerging area.Comment: Keynote Paper, 3rd International Conference on Advances in Computing, Communications and Informatics (ICACCI 2014), September 24-27, 2014, Delhi, Indi

Cloud Security : A Review of Recent Threats and Solution Models

The most significant barrier to the wide adoption of cloud services has been attributed to perceived cloud insecurity (Smitha, Anna and Dan, 2012). In an attempt to review this subject, this paper will explore some of the major security threats to the cloud and the security models employed in tackling them. Access control violations, message integrity violations, data leakages, inability to guarantee complete data deletion, code injection, malwares and lack of expertise in cloud technology rank the major threats. The European Union invested €3m in City University London to research into the certification of Cloud security services. This and more recent developments are significant in addressing increasing public concerns regarding the confidentiality, integrity and privacy of data held in cloud environments. Some of the current cloud security models adopted in addressing cloud security threats were – Encryption of all data at storage and during transmission. The Cisco IronPort S-Series web security appliance was among security solutions to solve cloud access control issues. 2-factor Authentication with RSA SecurID and close monitoring appeared to be the most popular solutions to authentication and access control issues in the cloud. Database Active Monitoring, File Active Monitoring, URL Filters and Data Loss Prevention were solutions for detecting and preventing unauthorised data migration into and within clouds. There is yet no guarantee for a complete deletion of data by cloud providers on client requests however; FADE may be a solution (Yang et al., 2012)