In Cloud computing environment, resources include virtual machine, CPU and Storage. These resources are accessed by tenants. Group key may be used to access the resources securely. Group key is constructed using tree by considering tenants in a group. In existing scenario, different key trees are formed even if tenants are common among multiple groups to access the resources. This paper address...

In the Software-as-a-Service model one single application instance is usually shared between different tenants to decrease operational costs. However, sharing at this level may lead to undesired influence from one tenant onto the performance observed by the others. Intentionally, the application does not manage hardware resources and the responsible OS is not aware of application level entities...

Software as a Service (SaaS) providers can serve hundreds of thousands of customers using sharable resources to reduce costs. Multi-tenancy architecture allows SaaS providers to run a single application and a database instance, which support multiple tenants with various business needs and priorities. Until now, the database management systems (DBMSs) have not had the notion of multi-tenancy, a...

Cloud computing is a trend of technology aimed at providing on-demand services with payment based on usage. To improve the use of resources, providers adopt multi-tenant approaches, reducing the operation costs of services. Moreover, tenants have irregular workload patterns, impacting in the guarantees of quality of service, mainly due to interference between the tenants. This paper proposes an...

Multi-tenancy is one of the most important concepts for any Software as a Service (SaaS) application. Multi-tenant SaaS application serves a large number of tenants with one single application instance. Complex SaaS application that serves significant number of tenants could have a huge number of customizations with complicated relationships, which increases the customization complexity and red...

Multi-tenant main memory index is an important tool to accelerate data access to software as a service. Establishing main memory indexes for each tenant occupies lots of memory space and results in performance bottleneck. The data schemas and access patterns of different tenants are similar, which provides the conditions for tenants storing their index entries with shared structure in main memo...

Our objective was to evaluate the acceptability of a comprehensive smoke-free policy among low-income tenants in a group of subsidized, multiunit buildings. We conducted a mixed-methods evaluation that included questionnaires mailed to 839 tenants and follow-up telephone interviews with 23 tenants who were current, former, and never smokers. Most never and former smokers supported the policy, c...

A multi-tenant database is the primary characteristic of SaaS, it allows SaaS vendors to run a single instance application which supports multiple tenants on the same hardware and software infrastructure. This application should be highly customizable to meet tenants’ expectations and business requirements. This paper examined current solutions on multi-tenancy, and proposed a new meta-data dri...

Since energy-related costs make up an increasingly significant component of overall costs for data centers run by cloud providers, it is important that these costs be propagated to their tenants in ways that are fair and promote workload modulation that is aligned with overall cost-efficacy. We argue that there exists a big gap in how electric utilities charge data centers for their energy cons...

This article presents the results of a survey carried out in spring 2012 to determine the level of housing costs incurred by Austrian households. The housing cost survey shows that the share of housing costs borne by homeowners (loan repayment plus operating expenses and energy costs) accounts for 25% (median: 19%) of their net household income and is thus far lower than that borne by tenants (...