Hierarchical Policy Framework

NETQOS Hierarchical Policy Framework

Policy abstraction levels

QoS policies in NETQOS are specified in a hierarchical way considering different abstraction levels (business, intermediate, operational). To support mapping between the actor’s policies on different abstraction levels, the NETQOS system uses ontologies to describe the policy refinement and transformation (Policy Continuum) between the layers.
NETQOS policies at the different levels layers:

  • Business policies (high-level or actor-oriented policies),
  • Intermediate QoS policies (unified specifications) and
  • Operational or technology oriented policies (QoS mechanisms of management entities).

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The NETQOS hierarchical policy management supports automated configuration and adaptation of policies according to preferences of different actors considering SLAs.

NETQOS Policies and SLA

The SLA rules describe objectives and restrictions for the parameters of the policy rules, for instance usage of specific QoS mechanisms, handling of QoS anomalies, service degradation options and QoS parameter thresholds.
Similar to the policy definition, the syntax and semantic of the SLA’s objectives can be represented using an ontology or specific rule oriented language. More generic ontology based approaches for formal semantic specification, such as OWL and SWRL  can be also used to specify SLA rules and map their content to corresponding business level policies.

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NETQOS Business policies

The business policies for automated QoS configuration depend on the particular QoS management scenario and application. They are processed by APM considering the ontology descriptions and restrictions of the SLAs for the particular actor.

 For NETQOS scenarios different types of business policies have been defined:

  • QoS reservation policies for specific application traffic considering network context (X.641  specification);
  • Bandwidth reservation policies;
  • Measurement and monitoring policies.


The internal presentation of the business policies is structured based on generic and specific policy content:

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Using semantic operations and SWRL rules, the NETQOS business policies are translated by the POLD component into unified intermediate policies and stored in the common repository.

Intermediate policies

Intermediate policies are based on a common (unified) QoS vision considering the IETF QoS Policy Framework concepts using "condition and action" paradigm (see RFC 3644 [8]) and the NETQOS enhancements of the IETF policy information model for heterogeneous network environment [19].
Intermediate policies include policy identification and type, QoS request and time requirements, as well as references to ontology, SLA and actor descriptions, policy conditions, actions, functions and parameters used to present the required QoS. They are used by the NETQOS components for:
Policy monitoring and validation (MoMe component);
Policy adaptation, optimization and translation into operational policy (APA component).
The intermediate policies are translated by APA into XACML (eXtensible Access Control Markup Language) or XML based operational policies, which can be applied for different kind of heterogeneous devices (routers and/or Transport level entities).

Operational policies

The XACML / XML policies include the generic parameters for the device and technology dependent configuration of QoS mechanisms by the NetAgent / TranAgent at the management entities, i.e. the heterogeneous devices (routers / Transport entities). In particular, the policy parameters are based on the topology (source and destination addresses), the specific QoS mechanisms and QoS configuration information.

Interactions of the NETQOS components in respect of the different kind of policies:

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