AWS Series — What is Availability Zones and Regions
This is the most basic concept that everyone working on Amazon Web Services cloud should be aware of.
What is AWS Global Infrastructure?
The AWS has 31 Regions and 99 Availability Zones. This number can increase as they expand their data centers.
What is Region?
The region is simply the location. It can be London, Ohio etc., It is the Physical location.
A Region is a geographical area. Each region consists of 3 or more Availability Zones.
What is Availability Zone?
It is a data center. The Data Center is nothing but a building filled with servers. It has rows and rows of servers. These are in data halls. They have multiple data halls per data center depending on the data center architecture
An Availability zone may be several data centers, but because they are close together within certain mile radius, they are counted as one Availability Zone. Every Availability Zone is around 100kms radius.
What are Edge Locations?
Edge locations are the endpoints for AWS that are used for caching content.
Typically, this consists of cloudFront, Amazon’s content delivery network(CDN). There are many more edge locations than Regions. Currently, there are over 215 edge locations.
Why do we need them?
Suppose a multi national company has the customers from different locations and there is lot of content to be loaded in the websites let us say videos. It buffers a lot if we try to access something which resides in the data center that is far away. In order to best improve the customer experience, they have the edge locations, which caches the content and loads the data to the customer from the nearest location. Customer will never actually find the difference if it is loading from the edge location or any data center. For this purpose, Amazon uses Cloud Front which is the CDN.
Summary
- A Region is a physical location in the world that consists of two or more Availability Zones(AZs).
- An AZ is one or more discrete data centers — each with redundant power, networking and connectivity — housed in separate facilities.
- Edge Locations are endpoints for AWS that are using for caching content. Typically, this consists of CloudFront, Amazon’s CDN.
