| Acknowledgments | 第4-8页 |
| Abstract | 第8-9页 |
| 中文摘要 | 第10-20页 |
| CHAPTER 1. INTRODUCTION | 第20-41页 |
| 1.1 Cloud Computing | 第20-28页 |
| 1.1.1 Types of Cloud Computing Services | 第21-22页 |
| 1.1.2 Cloud Service Providers | 第22-26页 |
| 1.1.3 Deployment Models | 第26-28页 |
| 1.2 Teaching and Learning System in Cloud | 第28-32页 |
| 1.2.1 Cloud-based Teaching and LearningTools | 第28-30页 |
| 1.2.2 Cloud Computing Benefits | 第30-31页 |
| 1.2.3 Challenges and Solutions | 第31-32页 |
| 1.3 Availability in Cloud | 第32-34页 |
| 1.3.1 Redundancy through Replication | 第32-33页 |
| 1.3.2 Load Balancing Techniques | 第33-34页 |
| 1.4 Motivation of the Research | 第34-35页 |
| 1.5 Statement of the Problem | 第35-36页 |
| 1.6 Objectives of the Research | 第36-37页 |
| 1.7 Significance of the Research | 第37-39页 |
| 1.8 Scope of the Research | 第39-40页 |
| 1.9 Organization of the Thesis | 第40-41页 |
| CHAPTER 2. LITERATURE REVIEW | 第41-56页 |
| 2.1 Web-based Teaching and Learning System | 第41-46页 |
| 2.1.1 Functional Components in Web-based Teaching and Learning System | 第42-46页 |
| 2.2 Cloud-based Teaching and Learning System | 第46-52页 |
| 2.2.1 Cloud-based Teaching and Learning Architecture | 第47-50页 |
| 2.2.2 Benefits of the Cloud-based Teaching and Learning Architecture | 第50-52页 |
| 2.3 Fault Tolerance Technology in the Cloud | 第52-55页 |
| 2.3.1 Virtualization Fault Tolerant Methodology | 第53-55页 |
| 2.4 Summary | 第55-56页 |
| CHAPTER 3. PRELIMINARIES | 第56-74页 |
| 3.1 Key Concepts and Definitions of Availability | 第56-60页 |
| 3.1.1 Instantaneous (or Point) Availability, A(t) | 第56-57页 |
| 3.1.2 Steady-state Availability, A(∞) | 第57-58页 |
| 3.1.3 Inherent Availability, A_I | 第58页 |
| 3.1.4 Average Up-time Availability (or Mean Availability), A | 第58页 |
| 3.1.5 Achieved Availability, A_A | 第58-59页 |
| 3.1.6 Operational Availability, A_o | 第59页 |
| 3.1.7 Causes of unavailability | 第59-60页 |
| 3.2 Cloud Data Replication | 第60-64页 |
| 3.2.1 Array-based Replication | 第60-61页 |
| 3.2.2 Network-based Appliances Replication | 第61页 |
| 3.2.3 Host-based Replication | 第61-62页 |
| 3.2.4 Synchronous Replication | 第62-63页 |
| 3.2.5 Asynchronous Replication | 第63-64页 |
| 3.3 Related Essentials of Redundancy in Cloud | 第64-68页 |
| 3.3.1 Snapshots | 第64-65页 |
| 3.3.2 Hardware RAID | 第65-66页 |
| 3.3.3 Erasure coding Vs. Replication | 第66-68页 |
| 3.4 Load Balancing in Cloud | 第68-73页 |
| 3.4.1 Static Load Balancing Algorithms | 第71页 |
| 3.4.2 Dynamic Load Balancing Algorithms | 第71-73页 |
| 3.5 Summary | 第73-74页 |
| CHAPTER 4. HIGH AVAILABILITY ASSURANCE REPLICATION STRATEGY | 第74-93页 |
| 4.1 System Model and Assumptions | 第75-78页 |
| 4.1.1 Modeling Block Availability | 第76-77页 |
| 4.1.2 Mode ling File Availability | 第77页 |
| 4.1.3 Characterizing Node Availability | 第77-78页 |
| 4.2 Proposed High Availability Assurance Replication Strategy | 第78-84页 |
| 4.2.1 Which data files and When to Replicate | 第78-80页 |
| 4.2.2 Determining the Number of New Replicas | 第80-82页 |
| 4.2.3 How to Place New Replicas in Cloud Storage | 第82-83页 |
| 4.2.4 High Availability Assurance Replication Algorithm | 第83-84页 |
| 4.3 Simulations and Performance Analysis | 第84-92页 |
| 4.3.1 Simulation Environment and Parameter Setup | 第86-87页 |
| 4.3.2 Performance Evaluation | 第87-92页 |
| 4.4 Summary | 第92-93页 |
| CHAPTER 5. EFFICIENT LOAD BALANCING APPROACH FOR VIRTUALMACHINES IN CLOUD ENVIRONMENT | 第93-107页 |
| 5.1 Mathematical Formulation of Job Allocation Problem on Various VMs | 第93-95页 |
| 5.2 Proposed Virtual Machine Load Balancing Algorithm | 第95-98页 |
| 5.3 Experimental Setup and Results | 第98-105页 |
| 5.4 Summary | 第105-107页 |
| CHAPTER 6. CONCLUSION AND FUTURE WORK | 第107-109页 |
| 6.1 Conclusion | 第107-108页 |
| 6.2 Future Work | 第108-109页 |
| REFERENCES | 第109-117页 |
| Extended Abstract | 第117-120页 |
| 中文扩展摘要 | 第120-122页 |
| Research Achievements during the Period of Study | 第122页 |
| Publication | 第122页 |
| Research Projects during Master's Degree Program | 第122页 |
