klientserveri

Klientserveri, or client–server architecture, is a distributed computing model that divides tasks between service providers (servers) and requesters (clients). Clients request resources or services—such as web pages or data—from servers, which supply resources, enforce security, and perform processing over a network.

Two main configurations are two-tier and multi-tier architectures. In a two-tier setup, a client talks directly to a server. In three-tier or n-tier designs, presentation, application logic, and data management run on separate servers, improving scalability and fault isolation. Modern deployments often use microservices and cloud-based architectures.

Common examples include web browsers and web servers, email clients and servers, and database clients and servers. The client–server interaction follows a request–response pattern, with stateless protocols improving scalability while state can be managed with sessions.

Advantages include centralized resource management, ease of maintenance, scalability, and cross-platform compatibility. Drawbacks include dependency on the network, latency, potential single points of failure in simple layouts, and complexity in large deployments.

Historically, client–server concepts emerged from mainframe time-sharing and evolved with personal computing, becoming dominant with the World Wide Web in the 1990s. Architectural styles propagated to three-tier designs and, later, to distributed microservices.

Security considerations cover authentication, access control, encryption for data in transit and at rest, and regular updates. Current trends feature cloud and edge deployments, containerization, orchestration, and multi-cloud environments.