| Introduction | | | | controls the entire Database management |
| Used in almost all automated library systems, client | | | | 5. Distributed database: The server and the client partly |
| server technology is the computer architecture. Client | | | | handle the Database management |
| Server technology is computer architecture for | | | | In a library environment there are two major |
| separating the application’s functions into two or | | | | applications for client/server: |
| more distinct parts. Client/Server technology divides | | | | 1) For an automated library system as the |
| functions into client (requestor) and server (provider) | | | | architecture- To facilitate use of this system a vendor |
| subsystems, with standard communication methods | | | | designs a system using client/server technology to |
| (such as TCP/IP and z39.50). To facilitate the sharing | | | | access multiple servers to improve productivity and to |
| of information between them, it divides the functions. | | | | bring together multiple product lines. |
| On the desktop computer the client presents and | | | | 2) To linking heterogeneous systems as an approach- |
| manipulates data. To store and retrieve protected data | | | | To facilitate transparent access a vendor designs a |
| the server acts like a mainframe. The machines can | | | | client to systems of other vendors and from others a |
| perform their duties to their best. | | | | server to facilitate transparent access to its system. |
| Characteristics | | | | Benefits |
| The main characteristics of Client Server Technology | | | | The benefits of client/server computing are as under |
| is as under- | | | | 1) In spite of changing the legacy application it is much |
| • By the differences in their performing tasks the | | | | easier to implement client/server |
| client and server can be differentiated from one | | | | 2) Move to rapid application development and new |
| another. | | | | technology like object oriented technology |
| • The client and server generally function on | | | | 3) For development and support it is a long term cost |
| different computer platforms. | | | | benefits |
| • One or more servers may be connected by the | | | | 4) To support new systems it is easy to add new |
| clients. | | | | hardware like document imaging and video |
| • Multiple clients may be connected by the servers | | | | teleconferencing |
| at the same time. | | | | 5) For each application it can implement multiple vendor |
| • Without affecting each other the client or server | | | | software tools |
| may be upgraded. | | | | Client/Server technology is proved much cost efficient |
| • By requesting a service the clients always initiate | | | | and feasible in a mainframe environment. |
| the dialogue. | | | | Concerns |
| In a client/server environment a client PC almost does | | | | The companies implement client/server technology on |
| the following: | | | | the following concerns- |
| • screen handling | | | | • Between the client and server where there are |
| • menu or command interpretation | | | | many levels of complexity and compatibility issues |
| • data entry | | | | • Since you will need to maintain the old system |
| • help processing | | | | (mainframe) and the new client server architecture |
| • error recovery | | | | development cost will rise in the short term |
| A server can be anywhere along the dividing line and | | | | • There are many layers of complexity and |
| with a broad range between the clients. Only the user | | | | compatibility issues between the client and server. |
| interface has been moved onto the client at one end; | | | | • Cost will rise in the short term since you will need |
| at the other end the database may be distributed. | | | | to maintain the old system (mainframe) and the new |
| Along the range there are at least five points: | | | | client server architecture development. |
| 1.Distributed presentation: The server and the client | | | | • Software’s competency such as tools of |
| partly handle the presentation | | | | security and management are not as mature as |
| 2. Remote presentation: The client handles or controls | | | | mainframe counterparts. |
| the entire presentation | | | | • With these tools takes time to become proficient. |
| 3. Distributed logic: The server and the client partly | | | | • At giving up control of a centralized computing |
| handle the application logic | | | | environment Information System departments may |
| 4. Remote data management: The server handles or | | | | draw back. |