Policy Server Guides › Policy Server Configuration Guide › User Directories › User Attribute Mapping › User Attribute Mapping Overview

User Attribute Mapping Overview

There are five types of user attribute mappings and two types of named expressions. The attribute mapping types are:

• alias
• group name
• mask
• constant
• expression

The named expression types are:

• virtual user attributes
• user classes

User attribute mappings are similar to named expressions, but there are important differences, as follows:

• Access
  • While some types of user attribute mappings are read only (R) and map to user attribute values that cannot be changed, other types of user attribute mappings are read/write (RW) and map to user attribute values that can be read or changed:

    Read Only (R): Designates a mapping whose target can be read, but not changed.

    Read/Write (RW): Designates a mapping whose target can be read or changed.

  • All named expressions are read only (R).
• Data Types
  • User attribute mappings map to user attributes that have specified data types.
  • Named expressions, when evaluated, result in specified data types.
• Visibility
  • User attribute mappings are not global and must be defined for each user directory to which they apply.
  • Named expressions are global and can apply to any user in any user directory.
• Prefix?
  • User attribute mappings follow the same syntax rules as user attribute names.
  • Named expressions follow the same syntax rules as user attribute names and have a prefix:
    • Virtual user attributes must begin with the "pound" sign (#).
    • User classes must begin with the "at" sign (@).

For a summary of these differences, see the following tables: