Describe Cloud Computing

Introduction to Cloud Computing

What is Cloud Computing?

  • Cloud Computing is the delivery of computing services over the internet.
  • Computing services include common IT infrastructure such as virtual machine, storage, databases, and networks.
  • Cloud services also expand the traditional IT offerings to include things like internet of Things (IoT), machine learning (ML), and artificial intelligence (AI).

Describe the Shared Responsibility Model

shared responsibility model

The Cloud Provider is always responsible for

  1. The physical datacenter
  2. The physical network
  3. The physical hosts

As a customer, you’ll responsible for

  1. The information and data stored in the cloud
  2. Devices that are allowed to connect to your cloud (cell phones, computers, etc.)
  3. The accounts and identities of the people, services, and devices within your organisation.

Your service model will determine responsibility for things like

  1. Operating systems
  2. Network controls
  3. Applications
  4. Identity and infrastructure

Define Cloud Model

Public CloudPrivate CloudHybrid Cloud
No capital expenditures to scale uporganisation have complete control over resources and securityprovides the most flexibility
applications can be quickly provisioned and deprovisioneddata is not collocated with other organisations’ dataorganisations determine where to run their applications
organisation pay only for what they usehardware must be purchased for startup and maintenanceorganisations control security, compliance, or legal requirements
organisation don’t have complete control over resources and securityorganisations are responsible for hardware maintenance and updates

Describe the Consumption-Based Model

When comparing IT infrastructure models, there are two types of expenses to consider: Capital Expenditure (CapEx) and Operational Expenditure (OpEx).

CapEx is typically a one-time, up-front expenditure to purchase or secure tangible resources. For example, a new building, repaving the parking lot, building a datacenter, or buying a company vehicle.

In contrast, OpEx is spending money on services or products over time. For instance, renting a convention center, leasing a company vehicle, or signing up for cloud services are examples of OpEx.

Cloud Computing falls under OpEx because cloud computing operates on a consumption-based model. You only pay for the IT resources you use. If you don’t use any IT resources this month, you don’t pay for any IT resources

This consumption-based model has many benefits, including:

  • No upfront costs.
  • No need to purchase and manage costly infrastructure that users might not use to its fullest potential.
  • The ability to pay for more resources when they’re needed.
  • The ability to stop paying for resources that are no longer needed.

Describe the Benefits of Using Cloud Services

Describe the Benefits of High Availability & Scalability in the Cloud

  • SLA. A Service Level Agreement (SLA) is the formal agreement between a service provider and customer that guarantee the customer a stated level of service.
    • 99%. 432 mins per month down time.
    • 99.9%. 43.2 mins per month down time.
  • Scalability.
    • Scalability refers to the ability to adjust resources to meet demand.
    • If you suddenly experience peak traffic and your systems are overwhelmed, the ability to scale means you can add more resources to better handle the increased demand.
    • The other benefit of scalability is that you aren’t overpaying for services. You only pay for what you use.
    • Scaling generally comes in two varieties: Vertical Scaling and Horizontal Scaling.
  • Vertical Scaling (Scale-up)
    • This is to add more CPUs or RAMs to the virtual machine.
  • Horizontal Scaling (Scale-out)
    • This is to add more virtual machines or containers to process.

Describe the Benefits of Reliability & Predictability in the Cloud

  • Reliability.
    • Reliability is the ability of a system to recover from failures and continue to function.
    • The Cloud by virtue of its decentralized design, naturally supports a reliable and resilient infrastructure.
  • Predictability.
    • Predictability in the cloud lets you move forward with confidence on performance and cost.
    • Performance.
      • Performance predictability focuses on predicting the resources needed to deliver a positive experience for your customers.
      • Autoscaling, load balancing, and high availability are just some of the cloud concepts that support performance predictability.
    • Cost.
      • Cost predictability is focused on predicting or forecasting the cost of the cloud spend.
      • You can track your resource usage in real-time, monitor resources to ensure that you’re using them in the most efficient way, and apply data analytics to find patterns and trends that help better plan resource deployments.

Describe the Benefits of Security & Governance in the Cloud

  • By establishing a good governance footprint early, you can keep your cloud footprint updated, secure and well managed.

Describe the Benefits of Manageability in the Cloud

  • Management of the cloud. This means manages your cloud resources,
    • Automatically scale resource deployment based on need.
    • Deploy resources based on a pre-configured template, removing the need for manual configuration.
    • Monitor the health of resources and automatically replace failing resources.
    • Receive automatic alerts based on configured metrics, so you’re aware of performance in real-time.
  • Management in the cloud. This means how you’re able to manage your cloud environment and resources.
    • Through a web portal.
    • Using a command-line interface.
    • Using APIs.
    • Using PowerShell.

Describe Cloud Service Types

azure shared responsibility

Describe Infrastructure as a Service (IaaS)

  • Infrastructure as a Service (IaaS) is the most flexible category of cloud services, as it provides you the maximum amount of control for your cloud resources.
  • In an IaaS model, the cloud provider is responsible for maintaining the hardware, network connectivity (to the internet), and physical security.
  • With IaaS model, you’re essentially renting the hardware in a cloud datacenter, but what you do with that hardware is up to you.

Use cases

  1. Life-and-shift migration.
  2. You’re setting up cloud resources similar to your on-prem datacenter, and then simply moving the things running on-prem to running on the IaaS infrastructure.
  3. Testing and Deployment.
  4. You have established configurations for development and test environments that you need to rapidly replicate.

Describe Platform as a Service (PaaS)

In a PaaS environment, the cloud provider maintains

  • Physical infrastructure
  • Physical security
  • connection to the internet
  • Operation Systems
  • Middleware
  • Development Tools
  • Business Intelligence services

User Cases

  1. Development framework.
  • PaaS provides a framework that developers can build upon to develop or customise cloud-based applications.
  1. Analytics or Business Intelligence.
  • Tools provided as a service with PaaS allow organisation to analyse and mine their data, finding insights and patterns and predicting outcomes to improve forecasting, product design decisions, investment returns, and other business decisions.

Describe Software as a Service (SaaS)

With SaaS, you’re essentially renting or using a fully developed application. Email, Financial software, messaging applications, and connectivity software are common examples of a SaaS implementation.

Use Cases

  1. Email and Messaging.
  2. Business productivity applications.
  3. Finance and expense tracking.

Reference