Cloud definition and how is working
Cloud is a general name given to a complex system created by services for data hosting, transportation, protection, caching and more that can deliver data with the help of the internet.
The term Cloud is more intensively used in the last years but what Cloud is doing, at a basic level takes place since the internet was born.
More companies are moving to Cloud nowadays, which means they transfer the data, databases, applications, and the services they give, on a server or servers that work together.
The reason for doing that is to give world wide accessibility to customers, easy data updates with the help of the internet and a better user experience using cache, backup and speed systems on complex networks across multiple countries.
Even if the Cloud seems to be like a place in the sky, for people without technical knowledge, storing things on Cloud or moving to Cloud means actually to move things to a physical server (which is still at the ground level in a building) somewhere in the world, usually into the country where we live or close to it and where the data will be accessed more often. For example, if a business is targeting a market from Asia, then the application used for this market will always be hosted and provided from a server or Data Center existed in Asia. This is not only for speed reasons but also because for some business, there are regulations that do not allow data to be stored and processed in a different country.
The only involvement of the sky in this process can be the satellites that receive the data from one place and send it to the other (like from an user to a server and vice versa). But even in this situation, most of the times, satellites are not involved, because data is transported on relatively short distances (like between a server and a website user) thru a wire infrastructure.
The structure of what is named Cloud was improved a lot in the last decade and became a very complex system.
The advantages of today Cloud:
- web applications can be stored on complex arhitectural systems that have multiple locations (that can cover multiple zones and regions) on different important cities in the world. In this way data is always accessible to the end user at the best possible speed
- be cashed at the server level to ensure speed (avoid database interrogations when the same data was already received and sent to the same or a different user)
- data back-up to ensure no information is ever lost
How is Cloud built today
One of the best platforms that provide the web services listed above and a lot more is AWS, part of Amazon, which first came on the market in 2006 and since then it became a very complex system with a much better improved arhitecture capable to deal with very difficult situations.
AWS infrastructure has multiple Availability Zones and each of this zones have at least one Data Center being capable to easy isolate faults generated by power lose or even natural disasters by connecting with other Availability Zones using high speed networks with private access.
When buying AWS services, it is the customer's responsability to choose the Availability Zone and the location for the data to be replicated on the Cloud.
Amazon will not change the Availability Zone or replicate a project on a different Data Center.
The customer has complete control in doing these replications and ensure that data replicated on a different zone follows the law under GDPR for Data protection and other similar ones.
Two or more Availability Zones create a AWS Region and 2 or more regions communicate between them using a AWS backbone network infrastructure.
For all this data to be easily migrated and replicated from one Data Center to another, AWS and other providers that give this type of services, use Containers. Read more about Containers and what they do into this article.
By using such a structure, a website will always be protected and accessible online no matter what problem will hit a data center.
When a Data Center fails, and a website that is stored in this Data Center is no longer available, a fast link will make the connection to the data replicated on a different Data Center. When the initial Data Center is restored and functional again, the connection is made from it again.
A web application is returned by the closest Data Center that has a replica of it based on the end user location (the geographical location). Because of the geographical distance, the speed used to access the website is at the highest level.
Imagine a website accessed from Germany but hosted in China. The download time will be a lot longer than if the website will be hosted on a city from Germany.
Until a few years ago, most of the websites were kept only on one server in one of the world cities. Sometimes, this servers got in maintenance mode because of some updates needed, or because they were hacked or simply fail to work for numerous reasons.
Because of that, customers from around the world were not able to access services stored on one of these servers until the problem was fixed, which was frustrating for both companies and users.
AWS is solving this problem with it's infrastructure creating a more stable, flexible and safe Cloud.