AWS Certified Cloud Practitioner
The six advantages of cloud computing for AWS Cloud Practitioner
AWS lists six advantages of cloud computing: trade fixed expense for variable expense, benefit from massive economies of scale, stop guessing capacity, increase speed and agility, stop spending money running and maintaining data centers, and go global in minutes. Each one names a problem of owning your own data center that the cloud removes.
What cloud computing is
AWS defines cloud computing as the on-demand delivery of compute power, database, storage, applications and other IT resources over the internet with pay-as-you-go pricing.
AWS owns and maintains the hardware. You provision and use what you need, and you pay only for what you use. You do not make a large upfront investment in hardware.
The six advantages
Trade fixed expense for variable expense: instead of investing heavily in data centers and servers before you know how you will use them, you pay only when you consume computing resources, and only for how much you consume.
Benefit from massive economies of scale: usage from hundreds of thousands of customers is aggregated in the cloud. That lets AWS reach higher economies of scale, which translates into lower pay-as-you-go prices than you could get on your own.
Stop guessing capacity: if you pick capacity before you deploy, you often end up with expensive idle resources or with too little capacity. In the cloud you use as much or as little as you need and scale up and down with a few minutes' notice.
Increase speed and agility: new IT resources are a click away, so the time to give them to developers drops from weeks to minutes. Experiments cost less and take less time.
Stop spending money running and maintaining data centers: you focus on your own customers and projects instead of racking, stacking and powering servers.
Go global in minutes: you can deploy an application in multiple Regions around the world with a few clicks, which gives customers lower latency at minimal cost.
How to tell them apart in a question
Look for the cause the question names. Aggregated usage across many customers points to economies of scale. Paying only for what you consume, with no upfront investment, points to fixed versus variable expense.
Idle servers or running out of capacity points to stop guessing capacity. Weeks becoming minutes points to speed and agility. Lower latency for users in other countries points to go global in minutes.
Deployment models: cloud, hybrid and on-premises
A cloud deployment runs every part of the application in the cloud. The application was either built there or migrated there.
A hybrid deployment connects cloud resources with existing resources that are not in the cloud, most often on-premises infrastructure.
An on-premises deployment, sometimes called private cloud, uses virtualization and resource management tools in your own data center. AWS says it does not provide many of the benefits of cloud computing, but some choose it for dedicated resources.
Where the exam catches people
- Believing economies of scale means you buy capacity in bulk: it means AWS aggregates usage from many customers, which lowers the pay-as-you-go price.
- Believing stop guessing capacity means buying extra capacity just in case: it means you scale up and down as needed instead of deciding capacity before you deploy.
- Believing trade fixed expense for variable expense is about lower prices: it is about paying only as you consume instead of investing upfront in data centers.
- Believing on-premises private cloud gives the same benefits as the cloud: AWS says it does not provide many of the benefits of cloud computing.