Policy-Driven Routing Management Using CIM - Computer Network Security - page 264

of use XML technologies, a more appropriate solution is to store routing
policies in an XML native database, as such we will describe at section 6.
- Policy Decision Point (PDP) in charge of interpreting the policies stored in the
policy repository, recuperating the set of rules for a particular PEP,
transforming them into a format that can be understood by the PEP, and
distributing them to the PEP.
- Policy Enforcement Point (PEP) is a component running on a border router that
can apply and execute the different policies received from the PDP.
The proposed architecture is independent of any particular policy, so it could be
used in the provision of security policies, QoS policies, or any other kind of policies.
5 Example of Routing Policy
The following example shows the mapping of the RoutingAction class of CIM
Schema into XML Schema (which follows the general steps explained in section 3):
<xs:complexType name="CIM_RoutingAction" >
<xs:complexContent>
<xs:extension base="CIM_PolicyAction" >
<xs:sequence>
<xs:element name="Action" type="xs:string"/ >
<xs:element name="AttributeAction" type="xs:uint16" />
<xs:element name="BGPAction" type= xs:uint16" />
<xs:element name="BGPValue" type="xs:string" />
<xs:element name="RemarkAction" type="xs:uint16" />
<xs:element name="RemarkValue" type="xs:string" />
<xs:element name="ConditioningAction" type="xs:uint16" />
<xs:element name="OtherConditioningAction" type="xs:string" />
<xs:element name="ConditioningValue" type="xs:string" />
</xs:sequence>
</xs:extension>
</xs:complexContent>
</xs:complexType>
As it is shown, the CIM class is mapped in a XS type extending the type
CIM_PolicyAction , and each class property is mapped into a different XS element.
The CIM_PolicyAction and basic types (i.e., string and uint16) are defined in other
XS documents.
A practical example of policy combining both routing concepts and QoS concepts
is the following one:
If (IP source address = 155.0.0.0/8) and (IP source Port = 80)
then changing the DSCP value = 40
Differentiated Services Code Point (DSCP) value is related with differentiation of
services in IPv4 and IPv6 network, as quality of services aspects. Therefore this rule
implies that all web traffic (port 80) from the A class 155.0.0.0/8 network will be