Module 1 - Cloud Concepts

Why Cloud Services?

Cloud Computing

  • Cloud computing = Delivery (wide ranges) of computing services over the internet (the cloud).
  • Cloud service provider = The company that delivering such services

Key Concepts

  • High Availability = Ability top keep service up and running for a long period of time
  • Scalability = Ability to increase/decrease resources for any given workload
    • Scale out = add additional resource
    • Scale up = add additional capability to existing resources
  • Elasticity = Automatic and dynamic scalability
  • Agility = Ability to react quickly
    • allocate/deallocate resource on-demand via self-service w/o manual intervention
  • Fault Tolerance = Ability to remain up & running  even a component or service no longer functioning 
    • archived by 'redundancy'
  • Disaster Recovery = Ability to recover from an event which has taken  down a cloud service
  • Global Reach = Ability to reach audiences in various regions around the globe 
  • Customer latency capability
    • Customers are experiencing slowness = customer are experiencing some latency 
    • Could caused by the service is not local to the customer
    • Could be solved by deploying services in data centers around the globe
  • Predictive cost consideration = Ability for user to predict cost incurs for cloud services they use
  • Technical skill consideration
    • User who expert in application they want to run without the need of skills to build & maintain underlying h/w & s/w infrastructure
  • Increased Productivity
    • Data center requires lots of h/w setup (called 'racking & stacking'), s/w patching
    • Cloud computing eliminates these tasks so IT department can focus on important business goals
  • Security
    • Cloud providers usually provide broad set of policies, technology, controls more than any single company can has on their own
  • See cloud computing terms for more

Economy of Scale

  • Ability to reduce cost and gain efficiency when operating at larger scale  vs. smaller scale
  • Cloud provider can acquire h/w at much lower cost and pass on that benefits to customers

CapEx vs. OpEx

  • Capital Expenditure (CapEx) = spending money on physical infrastructure up front and values reduce over time
  • Operational Expenditure (OpEx) = spending money on services or products now and being billed for them now
  • Consumption-based Model
    • Pay only what you use
    • No up-front cost/CapEx
    • Can pay more to get additional resource when needed and can stop paying when no longer need it

Types of Cloud Models

Public Cloud vs. Private Cloud

  Public Cloud Private Cloud
Data center Cloud provider owned Organization-owned
Ownership Cloud service provider The organization itself
Users Multiple organizations Within the organization
Access Public Single organization
Connectivity Over the internet Usually over private network
Skill to use No deep tech skill required Require deep tech skills to setup, manage, and maintain

Hybrid Cloud

  • Combined both Public and Private cloud
  • Some resources run on public cloud, some on private cloud
  • Organization retain the management control in private cloud
  • Use cases
    • Highly secured data or something that cannot put on public cloud e.g. due to legal reasons
    • Old specific hardware that can't be updated e.g. mainframe

Comparisons

Public Cloud Private Cloud Hybrid Cloud

Pros

  • No CapEx
  • Agility
  • Consumption-based
  • No maintenance
  • No deep skill required

Pros

  • Complete control over resources and security
  • Compliance achievable
  • Specific scenario achievable

Pros

  • Flexibility - most flexible
  • Costs - still can take advantage from public cloud
  • Control & Security - can still put in private cloud
  • Compliance still achievable
  • Specific scenario achievable

Cons

  • Security requirement may not be met
  • Compliance may not be met
  • Ownership - cannot manage as they wish
  • Specific scenario - legacy app or h/w

Cons

  • Up-front CapEx
  • Agility
  • Maintenance
  • Skills

Cons

  • Up-front CapEx
  • Costs
  • Skills - including make both operate together
  • Ease of management - should have guidelines on what on public or private cloud

Shared Responsibility Model

  • Public cloud advantages do not absolve the customer from protecting their users, applications, and service offering.
  • Shared responsibility model ensures cloud workloads are run securely and in a well-managed way.
    • Cloud provider is responsible for some aspect of the workload management.
    • Customer or end user is also responsible for other aspects
    • Both share a responsibility

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IaaS PaaS SaaS

Characteristics

  • Most basic but most flexible
  • Rent only IT infrastructure
  • No upfront cost

Characteristics

  • Provide environment for building, testing, and deploying s/w
  • Without worrying about underlying infrastructure
  • No upfront cost

Characteristics

  • Software that centrally hosted and managed e.g. Office 365
  • Usually licensed through monthly or annual subscription
  • No upfront cost

Common usage scenarios

  • Migrating workloads - easy to migrate from on-premise
  • Test and development environment - quicker to deploy
  • Website hosting - lower cost
  • Storage, backup, and recovery - more simplified

Common usage scenarios

  • Development framework - developer can build upon
  • Analytics or Business Intelligence - analyze and mine data

Common usage scenarios

  • Office 365
  • Skype
  • Microsoft Dynamics CRM Online

Comparisons

IaaS PaaS SaaS

Pros

  • No CapEx
  • Agility
  • Consumption-based
  • Skills - no deep technical to deploy & use
  • Cloud benefits - secured and HA
  • Flexibility - control to configure, manages h/w

Pros

  • No CapEx
  • Agility
  • Consumption-based
  • Skills - no deep technical to deploy & use
  • Cloud benefits - secured and HA
  • Productivity - focus on application development

Pros

  • No CapEx
  • Agility
  • Pay-as-you-go - monthly or yearly
  • Flexibility - data accessible from anywhere

Cons

  • user manages and maintains services they provision

Cons

  • Some limitations from PaaS

Cons

  • Software limitations - no or limited customizations