Independent clients, Getting started – Echelon LNS User Manual

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LNS Programmer's Guide

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Lightweight Client applications, or the LNS Server PC. Therefore network variables,

connections and monitor sets defined on the Network Service Device used by a remote
Full client application are shared only by other remote Full clients on the same PC that

are connected to the same network.

Independent Clients

If an application does nothing but perform monitor and control services, it does not need

to access the LNS network database, and thus does not need to connect to the LNS

Server. For this reason, LNS provides a server-independent mode. An application running
in server-independent mode is considered an Independent client application.

Independent client applications do not need the LNS Server to be running on the PC

containing the LNS global database, as shown in Figure 3.7. However, only applications

which can directly access the L

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network via an LNS network interface or

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IP channel can operate as Independent client applications. Note that in

Figure 3.7, the LNS Server PC is not attached to the network.

LNS Server PC

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Channel

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Device

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Device

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LNS Application PC with Network

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Figure 3.7 Network Communication As An Independent Client

Independent client applications can monitor and control monitor points that have been

previously created by a Full or Local client application, and automatically receive

network addressing updates from the network. They cannot create monitor sets, or add
monitor points to a monitor set, because Independent client applications cannot access

the LNS database. No objects can be added or removed by an Independent client

application, and most methods and properties unrelated to monitor and control are
unavailable. As noted, Independent client applications can only be used for monitor and

control operations.

For more information on monitor and control, see Chapter 9 of this document.

Getting Started

The first step to take when programming an LNS application is to select a client type and

initialize the LNS Object Server. Following that, you can use the network services

provided by LNS. Before doing so, you should review the rest of this document. For your

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