AZ-900:Describe cloud concepts ②

AZ-900の試験を英語で受けるに至り、翻訳なしで勉強をしてまとめていく勉強ノートです。

自身の復習用としても記事を書くつもりではありますが、同じように英語で受講予定＆翻訳なしでそのまま英語で勉強した方がやりやすい方の参考に少しでもなることが出来ればと思います。

日本語で勉強をしたい方は、こちらのサイトを是非参考にしてみてください：

https://qiita.com/fsd-jume/items/647aacf7147ece299fa1

# 学習内容
**Intro to cloud computing: Describing cloud concepts**
- [学習内容](#学習内容)
  - [Define cloud models](#define-cloud-models)

<a id="#define-cloud-models"></a>
## Define cloud models
The three main cloud models: private, public, and hybrid.

**Private cloud**
* What is it?
  * Cloud used by a single entity.
* Pros
  * Provides much greater control for the company and its IT department.
* Cons
  * Comes with greater costs
  * Comes with fewer of the benefits of a public cloud deployment
  * may be hosted from consumer's on site datacenter
  * may be hosted in a dedicated datacenter:
    * ex: third party that has deticated datacenter to consumer's company

**Public cloud**
* What is it?
  * Cloud that is built, controlled, and maintained by a third-party cloud provider.
* Pros
  * Unlike private cloud, anyone that wants to purchase cloud services can access and use resources.

**Hybrid cloud**
* What is it?
  * A computing environment that uses both public and private clouds in an inter-connected environment.
* Pros
  * Allows private cloud to adapt to increased, temporary demand by deploying public cloud resources.
  * Can be used for providing an extra layer of security
    * ex: choosing services to keep in public cloud or deploy to their private cloud infrastructure

|**Public cloud** | **Private cloud** | **Hybrid cloud** |
|-----------------|-------------------|------------------|
| CapEx doesn't scale up| Organizations' control over resources and security: yes| Provides most flexibility |
| The proces of creating, updating and deleting user accounts (provisioned and deprovisioned) can be quickly done | Data is not collocated with other organizations' data | Where to run applications are determinied by organizations |
| Organizations only pay for what they use | Startup and maintenance: hardwared must be purchased | Organizations' control over security, compliance, or legal requirements: yes|
| Organizations' control over resources and security: no | Organizations' responsibility for hardware maintenance and updates: yes|

**Multi-cloud**
* Uses two or more public cloud providers
* Manages resources and serucirty in all the environments

**Azure Arc**
* Set of technologies
* helps manage cloud environment
  * the cloud type doesn't matter: it can be private cloud in consumer's datacenter or public cloud solely on azure.

**Azure VMware Solution**
* can be used when migration to public or hybrid cloud from private cloud environment is needed.
* lets the consumer's VMware workloads in Azure with seamless integration and scalability

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AZ-900:Describe cloud concepts① はこちら：

https://qiita.com/fsd-lukapyon/items/0100596156d3abc7808e

AZ-900:Describe cloud concepts③ はこちら：

https://qiita.com/fsd-lukapyon/private/0324140f0b6c2034db68

AZ-900:Describe cloud concepts④ はこちら：

https://qiita.com/fsd-lukapyon/items/90ed9d652da29f19f06e

AZ-900:Describe cloud concepts⑤ はこちら：

https://qiita.com/fsd-lukapyon/items/3d489123078f765ccb87

AZ-900:Describe cloud concepts⑥ はこちら：

https://qiita.com/fsd-lukapyon/items/6b5e612044dd37b42386

AZ-900:Describe cloud concepts⑦ はこちら：

https://qiita.com/fsd-lukapyon/items/83390ae397ff8e7b8989

AZ-900:Describe cloud concepts⑧ はこちら：

https://qiita.com/fsd-lukapyon/items/abfc398d55bf28160b90

AZ-900:Describe cloud concepts⑨ はこちら：

https://qiita.com/fsd-lukapyon/items/4881ce9db481dd4173eb