Which architecture model requires that the client does not communicate directly with the data tier?

The correct answer is the three-tier client-server architecture, which is designed to separate the data management, application logic, and user interface into three distinct layers: the presentation tier (client), the application tier (middleware), and the data tier (database).

In this model, the client interacts primarily with the application tier rather than communicating directly with the data tier. This separation facilitates better management of the application, enhances security by restricting access to the database, and allows for scalability, as changes can be made to one layer without impacting the others. For example, if you upgrade or modify the database or the application logic, the client remains unaffected as it still communicates through the application tier.

In contrast, the two-tier architecture allows clients to interact directly with the data tier, which can lead to performance and security issues. The peer-to-peer architecture allows for direct communication between clients, which does not involve an intermediary responsible for separating the data layer. Microservices architecture involves independent services, where each service communicates over the network and may also access data directly, again making client-to-data tier communication possible. Thus, in a three-tier architecture, the client does not directly communicate with the data tier, making it the right answer.