Describe Cloud Concepts Flashcards
What is cloud computing ?
Cloud computing is the delivery of computing services over the internet. Computing services include common IT infrastructure such as virtual machines, storage, databases, and networking. 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
With a traditional corporate datacenter. The company is responsible for maintaining the physical space, ensuring security, and maintaining or replacing the servers if anything happens. The IT department is responsible for maintaining all the infrastructure and software needed to keep the datacenter up and running. They’re also likely to be responsible for keeping all systems patched and on the correct version.
With the shared responsibility model, these responsibilities get shared between the cloud provider and the consumer. Physical security, power, cooling, and network connectivity are the responsibility of the cloud provider. The consumer isn’t collocated with the datacenter, so it wouldn’t make sense for the consumer to have any of those responsibilities.
At the same time, the consumer is responsible for the data and information stored in the cloud. (You wouldn’t want the cloud provider to be able to read your information.) The consumer is also responsible for access security, meaning you only give access to those who need it.
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. You’re responsible for everything else: operating system installation, configuration, and maintenance; network configuration; database and storage configuration; and so on. With IaaS, you’re essentially renting the hardware in a cloud datacenter, but what you do with that hardware is up to you.
platform as a service (PaaS)
Platform as a service (PaaS) is a middle ground between renting space in a datacenter (infrastructure as a service) and paying for a complete and deployed solution (software as a service). In a PaaS environment, the cloud provider maintains the physical infrastructure, physical security, and connection to the internet. They also maintain the operating systems, middleware, development tools, and business intelligence services that make up a cloud solution. In a PaaS scenario, you don’t have to worry about the licensing or patching for operating systems and databases.
PaaS is well suited to provide a complete development environment without the headache of maintaining all the development infrastructure.
software as a service (SaaS)
SaaS places most of the responsibility with the cloud provider. Software as a service (SaaS) is the most complete cloud service model from a product perspective. With SaaS, you’re essentially renting or using a fully developed application. Email, financial software, messaging applications, and connectivity software are all common examples of a SaaS implementation.
While the SaaS model may be the least flexible, it’s also the easiest to get up and running. It requires the least amount of technical knowledge or expertise to fully employ.
When using a cloud provider, you’ll always be responsible for:
The information and data stored in the cloud
Devices that are allowed to connect to your cloud (cell phones, computers, and so on)
The accounts and identities of the people, services, and devices within your organization
The cloud provider is always responsible for:
The physical datacenter
The physical network
The physical hosts
The three main cloud models are:
private, public, and hybrid.
Private cloud
A private cloud is, in some ways, the natural evolution from a corporate datacenter. It’s a cloud (delivering IT services over the internet) that’s used by a single entity. Private cloud provides much greater control for the company and its IT department. However, it also comes with greater cost and fewer of the benefits of a public cloud deployment. Finally, a private cloud may be hosted from your on site datacenter. It may also be hosted in a dedicated datacenter offsite, potentially even by a third party that has dedicated that datacenter to your company.
Organizations have complete control over resources and security
Data is not collocated with other organizations’ data
Hardware must be purchased for startup and maintenance
Organizations are responsible for hardware maintenance and updates
Public cloud
A public cloud is built, controlled, and maintained by a third-party cloud provider. With a public cloud, anyone that wants to purchase cloud services can access and use resources. The general public availability is a key difference between public and private clouds.
No capital expenditures to scale up
Applications can be quickly provisioned and deprovisioned
Organizations pay only for what they use
Organizations don’t have complete control over resources and security
Hybrid cloud
A hybrid cloud is a computing environment that uses both public and private clouds in an inter-connected environment. A hybrid cloud environment can be used to allow a private cloud to surge for increased, temporary demand by deploying public cloud resources. Hybrid cloud can be used to provide an extra layer of security. For example, users can flexibly choose which services to keep in public cloud and which to deploy to their private cloud infrastructure.
Provides the most flexibility
Organizations determine where to run their applications
Organizations control security, compliance, or legal requirements
Multi-cloud
In a multi-cloud scenario, you use multiple public cloud providers. Maybe you use different features from different cloud providers. Or maybe you started your cloud journey with one provider and are in the process of migrating to a different provider. Regardless, in a multi-cloud environment you deal with two (or more) public cloud providers and manage resources and security in both environments.
Azure Arc
Azure Arc is a set of technologies that helps manage your cloud environment. Azure Arc can help manage your cloud environment, whether it’s a public cloud solely on Azure, a private cloud in your datacenter, a hybrid configuration, or even a multi-cloud environment running on multiple cloud providers at once.
Azure VMware Solution
Azure VMware Solution lets you run your VMware workloads in Azure with seamless integration and scalability.
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. A new building, repaving the parking lot, building a datacenter, or buying a company vehicle are examples of CapEx.
In contrast, OpEx is spending money on services or products over time. Renting a convention center, leasing a company vehicle, or signing up for cloud services are all examples of OpEx.
High availability
High availability focuses on ensuring maximum availability, regardless of disruptions or events that may occur.
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. Because the cloud is a consumption-based model, you only pay for what you use. If demand drops off, you can reduce your resources and thereby reduce your costs.
Scaling generally comes in two varieties: vertical and horizontal. Vertical scaling is focused on increasing or decreasing the capabilities of resources. Horizontal scaling is adding or subtracting the number of resources.
Vertical scaling
With vertical scaling, if you were developing an app and you needed more processing power, you could vertically scale up to add more CPUs or RAM to the virtual machine. Conversely, if you realized you had over-specified the needs, you could vertically scale down by lowering the CPU or RAM specifications.
Horizontal scaling
With horizontal scaling, if you suddenly experienced a steep jump in demand, your deployed resources could be scaled out (either automatically or manually). For example, you could add additional virtual machines or containers, scaling out. In the same manner, if there was a significant drop in demand, deployed resources could be scaled in (either automatically or manually), scaling in.
Reliability
Reliability is the ability of a system to recover from failures and continue to function. It’s also one of the pillars of the Microsoft Azure Well-Architected Framework.
The cloud, by virtue of its decentralized design, naturally supports a reliable and resilient infrastructure. With a decentralized design, the cloud enables you to have resources deployed in regions around the world. With this global scale, even if one region has a catastrophic event other regions are still up and running. You can design your applications to automatically take advantage of this increased reliability. In some cases, your cloud environment itself will automatically shift to a different region for you, with no action needed on your part. You’ll learn more about how Azure leverages global scale to provide reliability later in this series.
Predictability
Predictability can be focused on performance predictability or cost predictability. Both performance and cost predictability are heavily influenced by the Microsoft Azure Well-Architected Framework. Deploy a solution built around this framework and you have a solution whose cost and performance are predictable.
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. If you suddenly need more resources, autoscaling can deploy additional resources to meet the demand, and then scale back when the demand drops. Or if the traffic is heavily focused on one area, load balancing will help redirect some of the overload to less stressed areas.
Cost
Cost predictability is focused on predicting or forecasting the cost of the cloud spend. With the cloud, you can track your resource use 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. By operating in the cloud and using cloud analytics and information, you can predict future costs and adjust your resources as needed. You can even use tools like the Total Cost of Ownership (TCO) or Pricing Calculator to get an estimate of potential cloud spend.
Management of the cloud
Management of the cloud speaks to managing your cloud resources. In the cloud, you can:
Automatically scale resource deployment based on need.
Deploy resources based on a preconfigured 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
Management in the cloud speaks to how you’re able to manage your cloud environment and resources. You can manage these:
Through a web portal.
Using a command line interface.
Using APIs.
Using PowerShell.
