Uplink sessions – Echelon OpenLDV User Manual

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Extending xDriver

The events shown in Figure 15 that occur within the LNS application represent

a typical LNS application that opens a downlink session. Your application can

vary from these steps.
In addition, the events that occur within the lookup extension component in the

flow chart represent the minimal tasks that a lookup extension component must

perform during a downlink session. This flow chart refers to the methods that

you can use when programming your custom lookup extension component. For

more information about these methods, see Appendix C, Custom Lookup

Uplink Sessions

An xDriver session is considered an uplink session if an RNI initiates the session

by requesting a connection to an OpenLDV application. This request for

connection is usually caused when the RNI receives a message with a qualifying

message code.
For xDriver to receive the request, the xDriver Connection Broker must be

running. For information about the xDriver Connection Broker, see Starting the

Connection Broker on page 135.
There must also be at least one xDriver profile with uplink session handling

enabled for xDriver to receive the uplink session request. You can use the

OpenLDV xDriver Profile Editor to create an xDriver profile that has uplink

session handling enabled. Using the Profile Editor, you can assign the profile a

port, which the Connection Broker uses to listen for uplink session requests. The

profile handles all uplink session requests on that port. For more information

about xDriver profiles and the xDriver Profile Editor, see xDriver Profiles on page

134.
Figure 16 shows the application flow for a downlink session.

User Application

x.Profile.RNI

Lookup Extension

Connection Broker

OpenLDV

Application

Database

SmartServer

Figure 16. Uplink Session Overview

The application flow for an uplink session includes the following steps (see

1. An RNI (for example, a SmartServer) requests an uplink session. When

the request for connection is made, the Connection Broker receives an