Observations

• Implementing Availability, Fault Tolerance and Elasticity in our local data centers with limited budgets or resources is difficult to implement.
• So there exists a need where you get your infrastructural needs / application needs delivered as a Service (Similar to Electricity)

Terms

• Cloud Provider:
  • Is an Orgnaization that provides Cloud-Based IT resources.
  • Examples: Amazon, Microsoft, Google
• Cloud Consumer:
  • Is an Organization that has a formal contract/arrangement with Cloud Provider to use IT resources provided

Cloud Delivery Models

• To deliver the Cloud Based Services to the Cloud Consumers, there are three popular models
  • Infrastructure As A Service (IAAS)
    • Infrastructure from you
    • Needs from the customer will be RAW IT (Virtual Machine, Disk, Network Disk, Networking)
    • Once virtual infrastructure is created the cloud consumer will be the owner of resource and billing might start (depends on payment mode)
  • Platform As A Service (PAAS)
  • Software As A Service (SAAS)

Cloud Provider InfraStructure

• Will have data centers with lot of racks which in turn have lot of servers, Providers use these servers to provide IT Resources to the Consumers
• Cloud Providers provide the Services in two possible models

  • Single-tenant

  • Multi-tenant

• Multi-tenant is generally cheaper because cloud providers can effectively use their hardwares