Echelon LNS - Manual (Page 306)

LNS Programmer's Guide 292
and begins tracking the number of deficit credits. For more information on the
OnLicenseEvent event, see Tracking License Events on page 293.
If the number of deficit credits in use is reduced to zero, either by installing more LNS
Device Credits on the LNS Server PC, or by removing devices from the network, the
timer will reset and the LNS Server will return to normal operation. If the timer expires
or the number of deficit credits used exceeds the maximum, the LNS Server will no
longer operate. In this case, you must upgrade the license by purchasing more LNS
Device Credits from Echelon or a distributor. Since the LNS Server will not even be
operable, you will not be able to remove devices and regain LNS Device Credits at that
point.
The minimum purchase is 50 LNS Device Credits, plus the number of deficit credits you
are using. When you purchase the additional LNS Device Credits, the LNS Server
License Wizard will automatically suggest a value that is equal to 50 plus the number of
deficit credits currently used. It is the responsibility of the LNS application to warn users
when they are in deficit mode, so they can purchase more LNS Device Credits or remove
devices from the network, as appropriate.
Entering the Standard Mode
To enter the Standard Mode, an application must invoke the ObjectServer object's
SetCustomerInfo() method before it opens the Object Server. The method takes two
parameters, a customer ID and key, as follows:
ObjectServer.SetCustomerInfo CustomerID, CustomerKey
The CustomerID and CustomerKey values are printed on the back cover of the LNS
Application Developer’s Kit CD-ROM jewel case. Remember that if you do not call
SetCustomerInfo() to enter the Standard Mode, your application will remain in
Demonstration Mode.
NOTE: Some legacy LNS applications may still use the SetCapacity() method. These
applications will be automatically switched to use the Standard Mode described in this
chapter as soon as the method is called. At that point, the application will use the LNS
Device Credits on the LNS Server PC to determine how many devices can be installed on
the system, as opposed to using a separate capacity for each system.
Protecting Your Keys
It is very important to protect the integrity of your customer ID and customer key. This
information is confidential and should be guarded as securely as any other confidential
information that you use. Do not use the customer key or customer ID as any form of
product key.
Viewing License Status
LNS applications can determine a system’s current licensing status by reading the
System object’s CreditInfo property. This returns a CreditInfo object contains the
following licensing-related properties:
• DaysRemaining: The number of days remaining before the license
expires. If deficit credits are in use, the value of this property will be 14
or less. The special value of 255 is normal, indicating that no deficit