This section is allocated for describing the prominent and dominant software architecture patterns.

There are several weaknesses associated with monolithic applications:

• Scalability: Monolithic applications are designed to run on a single and powerful system within a process. Increasing the application's speed or capacity requires fork lifting onto newer and faster hardware, which takes significant planning and consideration.
• Reliability and availability: Any kind of faults or bugs within a monolithic application can take the entire application offline. Additionally, updating the application typically requires downtime in order to restart services.
• Agility: Monolithic code bases become increasingly complex as features are being continuously added, and release cycles are usually measured in periods of 6-12 months or more.

As already mentioned, legacy applications are monolithic in nature and massive in size. Refactoring and remedying them to be web, cloud, and service-enabled is bound to consume a lot of time, money, and talent. As enterprises are consistently pruning the IT budget and still expecting more with less from IT teams, the time for leveraging various architectural patterns individually or collectively to prepare and put modernized applications has arrived. The following sections detail the various promising and potential architecture patterns.