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HP Reliable Transaction Router User Manual

Page 24

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RTR Terminology

connection to the current router is maintained until the current

router fails or connections to it are lost.
All RTR software components can reside on a single node but

are typically deployed on different nodes to achieve modularity,

scalability, and redundancy for availability. During initial

application development, it can be convenient to use a single

physical node for all RTR roles and application software.
With different physical systems, if one node goes down or off

line, another router or backend node can take over application

processing. In a slightly different configuration, you could have

an application that uses an external applet component running

on a browser that connects to a client running on the RTR

frontend. Such a configuration is shown in Figure 1–8. In the

figure, the applet is separate from but connects to the client

application written to work directly with RTR.

Figure 1–8 Browser Applet Configuration

RTR Frontend

PC Browser

Web Server

Process

RTR Client
Application

Applet

VM-0826A-AI

The RTR client application could be an ASP (Active Server Page)

or a process interfacing to the webserver through a standard

interface such as CGI (Common Gateway Interface) script.
RTR provides automatic software failure tolerance and failure

recovery in multinode environments by sustaining transaction

integrity in spite of hardware, communications, application, or

site failures. This automatic failover and recovery of service can

exploit redundant or underutilized hardware and network links.

1–12 Introduction