Client/Server architecture is one of the central ideas of network computing. Most of today's business applications use this model, in which applications or data are requested from one computer (the client) and provided by another computer (the server). It is usually distinguished from the older, centralized, mainframe computer model by the use of small and dispersed computers. Today, however, even mainframe computers use the Client/Server architecture. The two types of Client/Server architecture are:
Two-tier architecture: the user interface is normally located in the user's desktop and the database processes are handled by a powerful server. The business rules could be handled either by the client or the server, depending on the application. While simple, this architecture offers less scalability and restricts flexibility.
Three-tier or multi-tier architecture: This is an evolutionary step which adds a middle-tier to increase flexibility. The middle-tier could include application servers, transaction processing monitors, and message queue
servers. It can provide a variety of services, including message queuing and database staging. This architectureimproves performance, flexibility, and scalability, and usually involves complex application development.
Today's Client/Server technology market is evolving fast, and staying on top of development requires professionals who can focus on technology and move in tandem with emerging trends. Since Client/Server technology marries a variety of new and old technologies, languages, and architectures, it is iimperative to partner with an organization who understands change, and has been through several architectural evolutions. PGS has extensive experience with a variety of platforms, from Mainframe to Open Systems, from JCL to Java, from "Monolithic" to "Distributed Object Computing." Let us leverage our expertise to your benefit. Our Client/Server offering also include: