Subject: policyRuleMandatory

From: Andrea Westerinen <[email-masked]>
Date: Tue, 16 Feb 1999 23:31:50 -0800

Since there was some discussion at the meeting, here is some additional
text.
Andrea

Current I-D text:
   This attribute indicates whether evaluation (and possibly action
   execution) of a policyRule is mandatory or not.  Its concept is
   similar to the ability to mark packets for delivery or possible
   discard, based on network traffic and device load.

   The evaulation of a policyRule MUST be attempted if the
   policyRuleMandatory attribute value is True.  If the
   policyRuleMandatory attribute value of a policyRule is False, then
   the evaluation of the rule is "best effort" and MAY be ignored.
     
     NAME             policyRuleMandatory
     DESCRIPTION     A flag indicating that the evaluation of the
                      policyConditions and execution of policyActions
                      (if the condition list evaluates to True) is
                      required.
     SYNTAX           Boolean
     OID              <to be assigned>
     EQUALITY        booleanMatch
     SINGLE-VALUED
     DEFAULT VALUE   TRUE

Explanation (perhaps this should be added to the text following the first
paragraph):

This attribute would be marked FALSE (not mandatory) in the following
scenarios:

1.  If it is acceptable for a policy evaluation engine or device to discard
this rule, based on work load.  
2.  If the rule's execution is optional due to timing or business process
guidelines.  For example, an administrator could define that the
installation of upgrade firmware for a set of devices is optional at the
present time.  At some point in the future, the administrator would update
the policyRule to make this upgrade "mandatory".

When error / event reporting is addressed in the Policy Framework, a
suitable event code should indicate "rule discarded".  This event would have
a very different semantic than that returned from the failure of a
"mandatory" rule.