NonStop Systems Introduction for H-Series RVUs

The Application Server Environment
NonStop Systems Introduction for H-Series RVUs—540083-001
3-5
Client/Server Architecture
In the client/server architecture, presentation services and part of the application logic
are placed on the PC, and the rest of the application logic and the database
management functions are placed on the Integrity NonStop server. It is a modular
structure based on separation of database-oriented and input-oriented functions and
takes full advantage of the processing power of the PC. This arrangement provides
several advantages:
•
Improves application performance by shifting some of the application workload
from the host to the workstation
•
Provides greater machine independence because client applications can be written
without regard for the underlying requirements of the host computer
•
Allows client applications to be written and data to be analyzed using standard off-
the-shelf software packages
•
Enables the end user to take advantage of easy-to-use graphical user interfaces
(GUIs)
•
Enables programmers to use the development tools available for their workstation
platform
As you will see later, the terms client and server are relative. A server that receives a
request from a client can then make a request of another server and, in effect, then
becomes a client of that server.
Figure 3-3. Client/Server Two-Tiered Structure
Server
Host computer
Presentation
Graphical user interface
Client
VST018.vsd
Tier 1
Tier 2
Business logic and
data management