Advanced Path and QoS Set Stacks comprise
Path Policy Sets and Quality of Service (QoS) Policy Sets. Path
policy sets specify traffic engineering while QoS policy sets specify
business priority. These policy sets contain policy rules.
An Advanced path or a QoS Stack consists of a
minimum of two default policy rules—Default Rule and Enterprise
Default Rule. Additional
policy rules can be added as required. A site can have a single
Path or QoS Stack attached to it at a time. An Advanced Path or
QoS Stack is a collection of Path or QoS policy sets that are stacked
in the order in which they are evaluated by a site.
A Path or QoS Stack can accommodate a maximum of four
policy sets and one default rule policy set. The policy sets in
a stack are ordered from left to right, with the left-most policy
set designated as the highest priority.
At any given time, only one Path or QoS Stack can be attached
to a site. You can add, change, or delete a policy set or a Path
or QoS stack at any time.
The relationship among Advanced Path Stacks, Policy Sets, and
Policy Rules is shown below.
Path and QoS policies simplify policy management. For example,
all applications may have the same priority across an entire enterprise,
but based on geographical regions, path policies may differ between