FREE ESSAY ON CLIENT/SERVER

CLIENT/SERVER

Client/server is the combination of three major technologies: Relational database
management systems (RDBMSs), networks, and client interfaces. Clients execute specific
local tasks with local resources. Servers provide shared resources and fulfill broad
tasks. Communication enables definition and completion of full work processes. 
Client/Server software Infrastructure
With competing paradigms-SQL databases, TP monitors, groupware, and distributed
objects-the middleware that connects clients to servers has grown dauntingly complex.
Client /server is the combination of three major technologies: relational DBMS, networks,
and client interface (usually GUI/PC based). Each element contributes to the overall
platform with very specific roles but is independent of the others in performing its
functions.
Advantages of the Client/Server Environment
Client/server is an open system. The advantages of this environment include:
Interoperability, Data integrity, Scalability, Accessibility, Performance, Security,
Adaptability, and Affordability.
Client/Server Architectures
The client/server software architecture is a versatile, message-based modular
infrastructure intended to improve usability, flexibility, interoperability, and
scalability as compared to a centralized, mainframe, time-sharing computing. A client is
defined as a requester of services and a server is defined as the provider of services. A
single machine can be both a client and a server depending on the software
configuration.
As a result of the limitations of file-sharing architectures, the client/server
architecture emerged. This approach introduced a database server to replace the file
server. 
Distributed Client/Server Architectures 
Distributed client/server systems serve environments with mixtures of heterogeneous
computers and networks, with users and objects everywhere. Distributed Object Database
Management Systems (ODBMSs) provide a mechanism for users to transparently access objects
anywhere, with the efficiency of native access via caching. The current generation of
distributed client/server computing allows information and resources and users to be
located anywhere, with transparent access among all of them.
These software architectures are based on the ORB technology, but go further than the
CORBA by using shared, reusable business models (not just objects) on an enterprisewide
scale.
Administrator tools have grown with the production use of ODBMS products to include
interactive and programmatic interfaces. These tool capabilities include:
? Moving objects and databases
? Dumping objects and databases to text interchange format and loading back
? Detaching databases from shared environments to portable ones
? Backing up online (which, of course, must be consistent across all databases in the
distributed client/server environment)
? Querying and forcing locks
? Tuning and performance and usage statistics
Client/Server in Large Enterprise Environments
In large enterprise environments, the performance of a two-tier architecture
client/server usually deteriorates as the number of online users increases. This is
primarily due to the connection process of the DBMS server. The data language used to
implement server procedures in SQL server type DBMSs is proprietary to each vendor.
Oracle, Sybase, Informix, and IBM, for example, have implemented different language
extensions for these functions.