A simple three-tier architecture consists of a web tier, an application or business tier, and the data tier. These tiers are ordinarily implemented using web servers, application servers, and databases, respectively.
The following figure illustrates tiered architecture on the cloud. This architecture supports auto scaling and load balancing of web servers and application servers. Further, it also implements a master-slave database model across two different zones or data centers (connected with high speed links). The master database is synchronously replicated to the slave. Overall, the architecture represents a simple way to achieve a highly scalable and highly available application in a cloud environment.
Cloud applications can be deployed at multiple locations. Typically, using AWS terminology, these locations are regions (that...
