2.1.5.1 Relationships Between TIF NP Service Actions

The following figure shows the relationships between NP Service Actions. The figure shows the precedence values (p) and shows which Service Actions are mutually exclusive in terms of Action Set configuration. In the diagram, Service Actions that are connected by lines are mutually exclusive. Service Actions that can be terminating actions are marked with asterisks.

Figure 2-10 NP Service Action Precedence

The mutual exclusion relationships can be explained as follows:

• NPRELAY and NPRLS – For the successful NP lookup case, must choose between Relay or Release
• CgPNSvcRqdCgpnNPRqd and NPRLS – CgPNNPRqdCgPNSvcRqd implies Relay behavior.

The precedence relationships can be explained as follows:

• CRP – CRP should be first since it is a special case and a terminating action.
• NPNRLS – NPNRLS is a special condition and a terminating action.
• NPRLS – Normal Release case; can be same precedence as normal Relay cases since they are mutually exclusive and cannot appear in the same action set with CgpnSvcRqd.
• NPRLS – NPRELAY can be the same precedence. The NP lookup status determines whether or not the second Service Action needs to be executed.
• CgPNSvcRqd, NPRELAY – normal relay case

The following principles apply to precedence relationships:

• Special NP Release cases are given higher precedence.
• Handlers that need to override conditions set by other handlers must be given lower precedence

The mutual exclusion relationships are enforced during vSTO configuration for TIF NP.