The Presence Access Layer (PAL) Enabler complements OMA Presence SIMPLE. PAL specifies logically interoperable abstractions known as Presence Aspects. Presence Aspects consolidate presence information based on one or more Presence Information Elements. PAL Presence Aspects are based on underlying rules that fully align with OMA Presence SIMPLE and Implementation Guidelines for OMA Presence SIMPLE. Further, Presence Triggers provide a mechanism for a presence aware service to execute a specified action (also specified by rules) when a change is detected for a corresponding Presence Aspect.

PAL Presence Context associates applicable presence aspects required to fulfill service function points with a presence aware service. This provides PAL Client's with a consolidated and determinate view of presence information. That is, a PAL Client need only interact with a specific subset of interoperable Presence Aspects and/or Presence Triggers as specified by the resolved Presence Context, for a given presence aware service or class of service.

The PAL Enabler includes the following features:

• PAL Client interraction including commoninteroperable Presence Aspects, and Presence Triggers based on consolidated presence information;
• Establish and resolve Presence Context associated with a presence aware service;
• Interworking with information owning enablers (e.g. OMA Presence SIMPLE);
• Privacy and security of information sources, and clients; AND
• Configuration and administration based on PAL Profile.