Chapter 1. Introduction 1.1 Backgrounds
Cloud computing [1] is an emerging topic recently, which is derived from the utility computing [2]. Cloud computing can provide services that is the most important characteristic.
When the user needs different types of the service from the cloud provider, it must support the required service of the user. Cloud providers apply the pay-as-you-go model for user usage. In
cloud computing, the Service Level Agreements (SLAs) [3] is an important issue in resource provisioning. In order to meet the SLAs, the cloud provider has to satisfy the user’s
requirement as possible as it can; otherwise, the cloud provider has to pay the penalty to users when the SLA is violated. Instances of SLAs include resources availability and servers stability and other utility services provided to users.
National Institute of Standards and Technology [4] defines cloud computing as a model,
“the cloud computing is a model for enabling ubiquitous, convenient, on-demand network
access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction.”[4] These shared computing resource pools can be quickly provided and released, at the same time minimizing management costs.
The cloud model improves the service availability; the cloud model consists of five essential
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characteristics: on-demand self-service, broad network access, resource pooling, rapid elasticity and measured service. In cloud computing, there are three service models:
infrastructure as a service (IaaS), platform as a Service (PaaS) and software as a Service (SaaS). The cloud model consists of four deployment models: the public cloud, the private cloud, the community cloud and the hybrid cloud. The cloud model improved the service availability; the cloud model consists of five essential characteristics, three service models and four deployment models, the model structure as shown in the Figure 2-1.
Figure 2-1 NIST defines model of cloud computing [4]
on-demand self-service
Users can acquire the resource from cloud computing capability, the user doesn’t need to
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interact with the cloud providers.
broad network access
The service of cloud provider is provided via network, the user can access the service of
the cloud provider through different platform (such as computer, smartphones and laptops).
resource pooling
The provider’s computing resources are pooled to serve the users, the cloud provider
assign physical and virtual resources according to the user demand.
rapid elasticity
Elasticity that can adjust the scale of resources according to the requirement of users, the resource of cloud computing seems endless. It depends on the demand to increase or decrease
the computing power.
measured service
The resource and service of cloud providers can automatically monitor and control the
user of resources, provide transparency of information between cloud provider and users
Software as a service (SaaS)
The cloud providers can provide computing resource to users, the users can use the cloud provider’s applications running on a cloud infrastructure and the applications can be access by multiple users.
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Platform as a Service (PaaS)
The cloud providers can provide computing resource to users; the users can deploy
user-created or acquired applications onto the cloud infrastructure.
Infrastructure as a Service (IaaS)
The cloud providers can provide computing resource to users; the users are able to
deploy and run software, which can include operating systems and applications.
public cloud
Public cloud provides service for the public, such as computing power, database, data
storage, network bandwidth and other services.
private cloud
Private cloud only provides services to a single organization and appointed the organization or the third party to manage. Private cloud is mainly to avoid excessive open in order to reduce the cloud services which may cause security problems from different users
using.
community cloud
Community cloud is made up of many organizations to share resources for support a specific community services (such as the medical and education cloud).
hybrid cloud
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Hybrid cloud is an organization that takes more than two different cloud service types, the hybrid forms can significantly increase the mobility application service, reduce the enterprise fully uses security risks of the public cloud.
1.2 Motivation
The profit of cloud providers is the cost obtained from the user, that profit is subtracted by the cost of the cloud provider and by the penalty of violated SLAs; such a cost includes the server hardware cost, the network communication cost, the administrator management cost and the energy consumption cost. Therefore, in order to make more profit, the cloud provider has to reduce the SLAs violation rate. In general, users submit jobs with deadline to the cloud provider. Once the job cannot be completed before deadline, the SLAs will be violated and the cloud provider must pay penalty to the user. Therefore, the cloud provider has to consider SLAs in order to guarantee resource stability and make more profits. When the user submits
more jobs to the cloud provider and the available resources of the cloud provider cannot satisfy the client’s requirement, the cloud provider has to lease resources from other cloud vendors to
deal with the user’s requirement for competing resources. Therefore, providers have to bid for resources from third-party cloud vendors [5]; the highest bidder will get resources, and pay the rent to cloud vendors.
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In general, the billing system of most cloud providers adopts fixed-price metrics.
However, the fixed-price metrics cannot guarantee efficient resource allocation for the client requests [6]. If cloud providers considers SLAs for designing a better billing systems, it will be able to cause more users to apply. In order to increase cloud provider’s income, the cloud provider must consider more characteristics in billing systems different from other cloud providers that guarantee SLAs to users. For above reasons, the cloud provider needs considering how to obtain more resources by auction mechanisms from cloud vendors and how to design a better billing systems, those mentioned issues should be considered.
1.3 Purpose
This thesis aim to make cloud providers without violating SLAs leasing more resources from cloud vendors, and competing jobs from users for receiving more jobs; therefore, above these reasons that cloud providers could making more incomes. In order to solve this problem, this study addresses an auction-based approach for dynamic resource provisioning and allocation, billing systems with considering SLAs for the user. The goal of this work is to satisfy the requirement of users and snatch resources from other vendors (ensure that income is more than expenditure), in order to prevent SLAs violation and maintains the reputation of the cloud provider. So, the contribution of this work includes: the auction-based approach for dynamic VM provisioning and allocation, billing systems with considering SLAs for the
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cloud provider and the user, an automatic resource-monitoring system, and the competing jobs system.
1.4 Thesis Organization
The rest of this thesis is organized as follows: Chapter 2 discusses related works, which include the cloud computing, the virtualization, billing system, the OpenStack, and the Nagios.
Chapter 3 describes the general auction and the reversed auction system architecture. Chapter 4 demonstrates the experimental results between the general auction and the reversed auction mechanism. Conclusions and future works are finally given in Chapter 5.
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