HP (Hewlett-Packard) Reliable Transaction Router Network Router User Manual


 
The Three-Tier Architecture
Figure 2–1 The Multitier Model
VM-0839A-AI
TR
FE
Terminals Frontends Routers Backends
Database
BE
Server
application
BE
Server
application
Client
application
TR
FE
Client
application
FE
Client
application
FE
Client
application
BE
Server
application
Client application processes run on nodes dened to have the
frontend role. This tier allows computing power to be provided
locally at the end-user site for transaction acquisition and
presentation.
Server application processes (represented by ‘‘Server application’’
in Figure 2–1) run on nodes dened to have the backend role.
This tier:
Enables the database to be distributed geographically
Permits replication of servers to cope with network, node or
site failures
Allows computer resources to be added to meet performance
requirements
2–2 Architectural Concepts