CLUSTERED BUSINESS LOGIC

Most sites try to handle scalability in the business layer. It is easier to handle scalability issues in the application server tier than in the database tier and is therefore advisable for large traffic sites to avoid interaction with the database as much as possible. To achieve this scalability at the application layer, new instances of the app server need to work seamlessly with existing instances, while providing an increase in performance. Clustering in this way allows all the application servers to believe they are all working on the same machine, even if they are not. Clustering the business logic in this way provides scalability without the performance hit caused by distributing business logic on several separate machines.