Using ‘Vendor Defined’ Optional Keywords

Since license policy in RLM is defined largely by license keys, a single binary version of your RLM-based application can support many different license policies. Once RLM is implemented, you can address ever-changing business rules by simply varying the type of license keys that you issue. RLM can support a wide range of licensing options and policies, many of which have been covered in previous articles on this blog under the “technology” heading.

This article briefly discusses a few optional license fields. The following license keywords can be classified as ‘vendor defined’ options as they are not used by RLM to determine policy, but can be accessed by your application to further restrict usage rights or present information to the end-user, such as in a start-up splash screen. These optional fields are factored into the license’s digital signature, so they are not editable by your customers. The fields are described below:

• Options= if your product has many separately-purchasable sub-features,
  you can list the ones which are licensed in this string. Some examples of how this might used include:  limit the number of database records that can be created or accessed, or the number of accounts that can be open, or the number of ports that can be accessed, etc.? This information can be entered into the ‘options = options_list‘  field and it must be parsed by your application.
• Contract= can be used to hold the customer’s purchase information or software agreement number. This can be displayed to the end-user to validate a support contract, etc.
• Issuer= could be used to identify the organization that issued the license, such as a third party distributor, or reseller, etc.
• Customer= used to identify the name of licensed customer and can be displayed by your application. Displaying this information in an “about box” or splash-screen can be an added deterent to unauthorized use. It is unlikely that Mega South-East Airlines would want to use a license that was issued to Main St. Bank.

• Type= used to identify the type of license and is a string containing one or more of the values:
  • “beta”
  • “demo”
  • “eval”

For example, type=”beta eval” or type=”eval”. The contents of the license type field are then used by your application to put your software into the appropriate mode of limited operation or usability.