School of Medicine

Besides MSIS Networking Group managing the hardware side of the School of Medicine servers, there are some client-server based services that the Networking Group manages.  The types of Client-Server services that the Networking Group provide and manage are listed on the left. They also manage the Norton Antivirus Corporate server system and the Microsoft System Management Server.

The Norton AV system ensures that all systems running a copy of the MSIS Managed Antivirus software are kept up-to-date.  The MS SMS system is used to publish applications for end-users to install, automatically install patches and updates to installed software and collect inventory on SoM systems.

Components in Client-Server Computing

Client-Server Computing is dividing into three components, a Client Process requesting service and a Server Process providing the requested service, with a Middleware in between them for their interaction.

• A Client Server Process usually manage the user-interface portion of the application, validate data entered by the user, dispatch requests to server programs. It is the front-end of the application that the user sees and interacts with. Besides, the Client Process also manages the local resources that the user interacts with such as the monitor, keyboard, workstation, CPU and other peripherals.
• On the other hand, the Server Process fulfills the client request by performing the service requested. After the server receives requests from clients, it executes database retrieval, updates and manages data integrity and dispatches responses to client requests. The server-based process may run on another machine on the network; the server is then provided both file system services and application services. Or in some cases, another desktop machine provides the application services. The server acts as software engine that manages shared resources such as databases, printers, communication links, or high powered-processors. The main aim of the Server Process is to perform the back-end tasks that are common to similar applications.
• Middleware allows applications to transparently communicate with other programs or processes regardless of location. The key element of Middleware is NOS (Network Operating System) that provides services such as routing, distribution, messaging and network management service. NOS rely on communication protocols to provide specific services. Once the physical connection has been established and transport protocols chosen, a client-server protocol is required before the user can access the network services. A client-server protocol dictates the manner in which clients request information and services from a server and also how the server replies to that request.

Various types of Servers

Disk and File Servers

The simplest form of servers are disk servers and file servers. With a file server, the client passes requests for files or file records over a network to the file server. This form of data service requires large bandwidth and can slow a network with many users.

Database, Transaction and Application Servers

• In database servers, clients passes SQL (Structured Query Language) requests as messages to the server and the results of the query are returned over the network. The code that processes the SQL request and the data resides on the server allowing it to use its own processing power to find the requested data, rather than pass all the records back to a client and let it find its own data as was the case for the file server.
• In transaction servers, clients invoke remote procedures that reside on servers which also contains an SQL database engine. There are procedural statements on the server to execute a group of SQL statements (transactions) which either all succeed or fail as a unit.
• Application servers are not necessarily database centered but are used to server user needs, such as. download capabilities from Dow Jones or regulating a electronic mail process. Basing resources on a server allows users to share data, while security and management services, which are also based in the server, ensure data integrity and security.