Client-server applications

Operating system resident Local applications Client-server applications Terminal emulation... 

The system is a typical client/server application that has its own main functions distributed on the LAN. The main functions are ... 

Most of the QSAR software listed in Box 23.3 is readily available in PC packages (e.g. IMP), or as client-server applications such as SAS and Pipeline Pilot. Some is freeware such as R or Orange. Unfortunately, much of the... 

The architecture of the MES application is shown in Figure 12.1. The system provides electronic batch record (EBR) functionality interfaced to a Laboratory Information Management System (LIMS). The system is a typical client-server application that has its own main funaions distributed on the LAN. The main functions are as follows ... 

The authors left Pfizer before RGate was complete however, it is our understanding that the initial implementation of RGate was deemed unacceptable and that it was eventually rewritten as a client-server application. 

A client/server application that is able to run inside an internet browser allows the users to access information from the imaging center like patients, procedures, reports, images associated to certain procedures. 

There are four main types of architectural options when implementing LIMS [6]. The first is the LAN (local area network) installation. In a multiple-site situation and through the standard client/server setup, the application would be hosted separately on a server at each site connected to PC clients. In this setup, the LIMS are installed on both the clients and the server. System administration is required at each facility. 

The first form led to client-server-styled systems, with the client combining user-interface and application logic and communicating via SQL requests with a database server that dealt with persistence, transactions, security, and so on. All communication involved database processing requests in SQL, and clients did not communicate with one another (except indirectly through shared data on the server). 

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. 

Even so, working HTML FORMs is somewhat primitive compared to other GUIs designed for high bandwidth interactivity. Many of these limitations have been relieved by the availability of Java, JavaScript, plugins and helper applications. Likewise, the availability of cookies has eased the limitations of the underlying user-context-free HTTP/HTML client-server model. 

A significant concept of the client server model is to extend the scope of the application to function in an enterprise-wide (possibly worldwide) network of interconnected LANs, which allow LIMS and other applications following the client/server model to be operable and administrable on a much larger scale than either LAN or central processing models. 

The client/server model often allows easier integration with other network applications (eg, finance, project management, or human resources) which typically operate in the environment of the server component of the client/server system. Client/server can be gradually introduced in an existing minicomputer environment, often with litde adverse incremental impact in terms of retraining and additional cost. 

There are inevitable interfaces between the application areas of the various sets of procedures and the computer systems to which they apply, as indicated in Figure 3.3. Client-server technology is typically the deciding factor in determining whether control system and laboratory application projects would be better served by IT system procedures. Another example might be that robotic systems used to automate laboratories would be better served by control system procedures. 

A complicating factor in the validation of LIMS is the wide variety in the scale of LIMS implementations. A LIMS can vary from a PC-based application in a single laboratory to a client/server-based system running across multiple sites on a company-wide area network with shared access to servers and multiple interfaces to other business systems. 

Good Practice for the use of computer systems in laboratory applications is now well established and is based on many years of experience. LIMS is simply another use of the power and flexibility of client/server or browser-accessed computerized systems. Therefore, it may be validated in a similar manner to other systems utilized within the pharmaceutical industry. Specifically, LIMS is... 

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 ... 

Set-up of the various system environments must be managed. Documentation must be developed to describe the hardware platform and installed software, including any network infrastructure. Hardware architecture design documentation should be prepared. A diagram should be included to illustrate the geographic distribution of any client-server hardware. Client-server software also needs to be defined. Clients are often referred to as either thick or thin, depending on whether they require substantial or minimal application-related software. Client-server software can be considered to consist of ... 

Operating System Operating system independent of the client or server application. GAMP level 1 software requiring version to be recorded (e.g., UNIX OS). 

Client Applications A client may be used for more than one application (e.g., MRP II, LIMS, and EMS). Each application will have an associated file set providing what is often referred to as its Graphical User Interface (GUI). File sets are usually built into standard client set-ups. Individual files may include some element of configuration. GAMP level 3 (e.g., Windows NT) and GAMP level 4 software require the version to be recorded, operability confirmed, and any configuration validated. Supplier Audit requirements are usually satisfied as part of the server application validation. 

The client/server nature of the SAP R/3 product means that the client-side SAP Graphical User Interface (GUI) must be aligned at the server version. To guarantee that all the 700 users of the application distributed on the five sites receive client version upgrades at the same time and align with the server version concurrently, an application has been installed to automatically distribute the software through the network (Microsoft SMS application). 

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