How to create a presence aging policy using Location Engine Config

Summary

This article shows how to create a presence aging policy in order to remove old presence data using Location Engine Configuration.

Prerequisites

You should know the information in the following articles:

• How to detect object presence using Location Engine Config
• How to get a list of types

Guide

Before you start, remember to:

• Make sure you have a valid dataset with the "UPresence" module installed.

• Set managed_base_type (see section 3 here for details) to UBase::Object before starting Location Engine Config.

• Start the Location Engine Configuration tool and check that the "Presence" tab is shown.

• Set some sensors to forward uplinks and/or chirps.

Setting up the policy

In Location Engine Config, create a policy as follows:

The following dialog appears:

Click OK and the policy is added to the list:

Rules about presence aging

Location aging policies (and location aging / location injection policies) are inherited according to the normal inheritance semantics, and can be overridden at descendants. If a policy is defined for a type T it will be inherited by any descendant U of T, unless U defines a policy, in which case the policy for T will be invisible to U and its descendants.

Presence aging policies can be defined for different cells. In general, smaller cells will take precedence over larger ones, but only after inheritance has been taken into account.

Example

If you have 2 Location Engine cells A and B, both containing uplink-forwarding sensors, define:

1. A presence aging policy for UBase::Object, Site, 90 seconds.
2. A presence aging policy for ULocationEngine::Tag, Cell A, 45 seconds.