Echelon LNS - Manual (Page 304)

LNS Programmer's Guide 290
Overview of LNS Licensing and Distribution
The LNS licensing model is based on LNS Device Credits. Each LNS Server PC contains
a number of LNS Device Credits, and you need one LNS Device Credit for each
application device you commission on a network. The LNS Object Server tracks these
LNS Device Credits automatically, and removes an LNS Device Credit from the credit
pool each time a device is commissioned. Credits may be purchased, added to servers,
and transferred between servers using the LNS Server utilities provided with the LNS
Application Developer’s Kit. LNS also provides a Demonstration Mode which does not
require the use of LNS Device Credits.
LNS Turbo Edition supports the standard, automated device credit management system,
as well as the legacy capacity-based licensing system used in LNS 1.0 and LNS 2.0.
Capacity-based applications built with LNS 1.0 or LNS 2.0 will use the LNS Device
Credit mechanism when running on LNS Turbo Edition.
The standard LNS Device Credit management feature offers several cost advantages for
the LNS developer. When you redistribute an LNS Server with your product with the
LNS Redistribution Kit, the LNS Server will include 64 LNS Device Credits by default.
After the end-user installs your product and reboots the target PC, the PC will have the
LNS Server installed, and will also have 64 LNS Device Credits by default. The LNS
Server redistribution is ready to run after the reboot, and does not require registration
with Echelon to operate. You should note that after installing your product and the LNS
runtime files, the user will need to initialize the LNS Server license to make the LNS
Device Credits visible to the LNS licensing utilities. Initialization can be accomplished by
opening a system with any LNS application, such as the LNS Server application.
Note that when you create your redistributable installation package with the LNS
Redistributable Maker utility, you can specify more than 64 LNS Device Credits (up to
512). See the Using the LNS Redistributable Maker Utility section later in this chapter
for more information on the utility.
If your application needs to commission devices, you must ensure that the
SetCustomerInfo() method has been called on the ObjectServer object before doing
so. You must do this before you open the system. This begins use of the standard LNS
Device Credit licensing mode. LNS requires that one LNS Device Credit is available each
time you commission a device on the network. When a device is decommissioned and
removed, an LNS Device Credit is returned back into the database. Thus, your end-user
does not get charged for deletions - only for the total number of devices managed by the
LNS Server. This is described in more detail later in the chapter.
NOTE: If you delete a network with the Remove() method, the network database will be
deleted. The LNS Device Credits consumed by all commissioned devices in that network
will be lost, unless those devices are first decommissioned. For more information on this,
see Removing Network Databases on page 255.
LNS Device Plug-in applications do not commission devices, and therefore developers of
LNS Device Plug-in applications do not need to be concerned about what licensing
management mechanism is in effect.
If end-users require more LNS Device Credits, they can use the LNS Server License
Wizard to purchase more LNS Device Credits from Echelon. Licensees of the LNS
Redistribution Kit product can also re-sell LNS Device Credits, subject to certain