In the previous section, we created a secure environment for our applications, by adding additional security to our VPCs. In this section, we will discuss VPC architectures, that can make the environments for our applications highly available. To make our environments highly available, we are going to deploy instances into multiple availability zones, and load balance the requests with elastic load balancing. Finally, we'll add additional resilience to our environment, by automatically scaling horizontally.
AWS is built on a global infrastructure, located in more than a dozen regions, including several countries in Europe and Asia, as well as Australia, the United States, Canada, and Brazil.
Each region is divided up into separate physical areas, in what AWS calls availability zones, or just AZs. The data centers are built in small, fault isolated clusters, in these availability zones, which are typically tens of miles apart. This makes a regionwide...