Client-server architecture

Use a three-tier client-server architecture. All business logic must be in the middle tier, presentation and dialog on the client, and data services on the server. In this way you can scale the application server processing independently of persistent storage. 

The three-tiered architecture turns the disadvantages of the client-server architecture into its advantages ... 

The three-tiered architecture is much more complex than a client-server architecture. 

The considerations for designing stress and capacity tests for a CDS will be discussed here and will be based on the client-server architecture shown in Figure 20.3. Note that all aspects of the system that need to be tested must be dehned in the system specihcation documentation. 

New pocket portals, using WAP or Blue Tooth technology, is also becoming an attractive option. However, a cautionary note needs to be registered with the heightened importance of system security and the risks of transmitting data over open systems. Biometrics and encryption are potential solutions. Also, audit trails need to be consistent across the range of software models adopted, especially client-server architectures and hand-held IPCs. 

Diagrammatic representation of the major hardware components of the system Client/server architecture Hardware component interfaces... 

Database applications can be installed on stand-alone PCs, host computers, or may have client server architecture. The hardware platform supporting the application requires qualification. Hardware testing (Installation Qualification) should include ... 

Figure 9.17. Reagent Selector—an example of a chemical data mart. Various components of the system are shown, including the data sources, the daemon program that automatically updates the mart, the concordance database, and the client/server architecture, which is implemented in a three-tier system.

Client-Server Architecture. A computer architecture in which a "server" computer (usually a larger and faster machine at a central location) runs programs that communicate over a network with numerous workstations or "client" machines that reside in offices and laboratories. The server computer performs heavy duty computing tasks such as database searching and molecular and data modeling, in response to commands from the users of the client comvuters. It then communicates the results back to the client machines. There, depending on whether the client is "thick" (a... 

Multi-tier Architecture. An expansion of a client-server architecture to include a middle layer of software. The middle tier may run on a computer different from either the client or server computers. The middle tier isolates the client and server programs, so that changes in either of them do not require corresponding changes in the other. The middle tier acts as to receive, authenticate, and transform data as it passes between client and server computers. To make middle tier software easy to change and maintain, it is often written in Java, a modem object-oriented computer language that is available free on most of today s computer platforms. 

Client-Server Architecture refers to a two-tier architecture model where client (user interface, input logic visualization) and server (business logic, database) are separated from each other and are connected via a computer network. 

N-Tier Architecture (multitier architecture) is a software architecture model where multiple software components serve different purposes and are physically separated, such as client-server architectures. 

Fig. 8.5 Software-enabled assay development. The CiphergenExpress Software with Data Manager and Biomarker Analysis Modules Isa relational database system with a client-server architecture designed for automated sample tracking and advanced data analysis. After identification and selection of clusters for meaningful data reduction, univariate and multivariate data analysis tools are used for the detection of single and multiple...

It is clear that one of the reasons ERP tools became so successful was that they were able to take advantage of improvements in the client/server architecture and in middleware. The general movement to the client/server platform in the late 1980s meant that firms could reduce the cost of a highly centralized configuration in favor of a more flexible client/server setup. The C/S configuration preferred by most ERP vendors is that of the standard three-tier C/S platform, which consists of a presentation server, connected to the application server, which is in turn connected to the database... 

Client/server architectures can be characterized by how the applications are distributed between the client and the server. In a two-tier architecture, the application logic is placed on either the cUent or the server undivided or split into two parts, which are placed on the client and the server respectively. In most cases, the presentation logic and the application logic are placed on the client side and the data logic is placed on the server side. Examples of two-tier C/S systems are file servers and database servers with stored procedures. Figure 5 shows a two-tier architecture. 

Such shared CAD systems use a common database. This is usually accessible from the individual CAD stations through a client-server architecture (Figure 26). Usually an Engineering Data Management System (EDMS), implemented in conjunction with a CAD system, is used. 

Figure 26 Shared CAD System with a Common Database and a Client-server Architecture.

Modem CMMs are in general designed as a client/server architecture. The CMM itself is a server offering measuring tasks, e.g., moving... 

The client-server architecture strongly separates the clients from the servers, allowing them to be developed... 

The technology evolution—personal computers, in-memory processing for advanced analytics, client/server architectures to support networked employees, increased global coimectivity, and e-commerce and business-to-business connectivity— was a steady drumbeat for process innovation and redefinition. These pioneers remember when memos were written by hand, letters were mailed through interoffice mail, and the phone was hardwired to the office wall. 

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